diff --git a/test/api/v3/integration/challenges/GET-challenges_group_groupid.test.js b/test/api/v3/integration/challenges/GET-challenges_group_groupid.test.js
index 9dcbbdcd5d..3f116d833d 100644
--- a/test/api/v3/integration/challenges/GET-challenges_group_groupid.test.js
+++ b/test/api/v3/integration/challenges/GET-challenges_group_groupid.test.js
@@ -27,22 +27,38 @@ describe('GET challenges/group/:groupId', () => {
       challenge2 = await generateChallenge(user, group);
     });
 
-    it('should return group challenges for non member', async () => {
+    it('should return group challenges for non member with populated leader', async () => {
       let challenges = await nonMember.get(`/challenges/groups/${publicGuild._id}`);
 
       let foundChallenge1 = _.find(challenges, { _id: challenge._id });
       expect(foundChallenge1).to.exist;
+      expect(foundChallenge1.leader).to.eql({
+        _id: publicGuild.leader._id,
+        profile: {name: user.profile.name},
+      });
       let foundChallenge2 = _.find(challenges, { _id: challenge2._id });
       expect(foundChallenge2).to.exist;
+      expect(foundChallenge2.leader).to.eql({
+        _id: publicGuild.leader._id,
+        profile: {name: user.profile.name},
+      });
     });
 
-    it('should return group challenges for member', async () => {
+    it('should return group challenges for member with populated leader', async () => {
       let challenges = await user.get(`/challenges/groups/${publicGuild._id}`);
 
       let foundChallenge1 = _.find(challenges, { _id: challenge._id });
       expect(foundChallenge1).to.exist;
+      expect(foundChallenge1.leader).to.eql({
+        _id: publicGuild.leader._id,
+        profile: {name: user.profile.name},
+      });
       let foundChallenge2 = _.find(challenges, { _id: challenge2._id });
       expect(foundChallenge2).to.exist;
+      expect(foundChallenge2.leader).to.eql({
+        _id: publicGuild.leader._id,
+        profile: {name: user.profile.name},
+      });
     });
   });
 
@@ -76,13 +92,21 @@ describe('GET challenges/group/:groupId', () => {
         });
     });
 
-    it('should return group challenges for member', async () => {
+    it('should return group challenges for member with populated leader', async () => {
       let challenges = await user.get(`/challenges/groups/${privateGuild._id}`);
 
       let foundChallenge1 = _.find(challenges, { _id: challenge._id });
       expect(foundChallenge1).to.exist;
+      expect(foundChallenge1.leader).to.eql({
+        _id: privateGuild.leader._id,
+        profile: {name: user.profile.name},
+      });
       let foundChallenge2 = _.find(challenges, { _id: challenge2._id });
       expect(foundChallenge2).to.exist;
+      expect(foundChallenge2.leader).to.eql({
+        _id: privateGuild.leader._id,
+        profile: {name: user.profile.name},
+      });
     });
   });
 });
diff --git a/test/api/v3/integration/challenges/GET-challenges_user.test.js b/test/api/v3/integration/challenges/GET-challenges_user.test.js
index 8b6a279045..21ae0aa96b 100644
--- a/test/api/v3/integration/challenges/GET-challenges_user.test.js
+++ b/test/api/v3/integration/challenges/GET-challenges_user.test.js
@@ -5,7 +5,7 @@ import {
 } from '../../../../helpers/api-v3-integration.helper';
 
 describe('GET challenges/user', () => {
-  let user, member, nonMember, challenge, challenge2;
+  let user, member, nonMember, challenge, challenge2, publicGuild;
 
   before(async () => {
     let { group, groupLeader, members } = await createAndPopulateGroup({
@@ -18,7 +18,7 @@ describe('GET challenges/user', () => {
     });
 
     user = groupLeader;
-
+    publicGuild = group;
     member = members[0];
     nonMember = await generateUser();
 
@@ -33,6 +33,16 @@ describe('GET challenges/user', () => {
 
     let foundChallenge = _.find(challenges, { _id: challenge._id });
     expect(foundChallenge).to.exist;
+    expect(foundChallenge.leader).to.eql({
+      _id: publicGuild.leader._id,
+      profile: {name: user.profile.name},
+    });
+    expect(foundChallenge.group).to.eql({
+      _id: publicGuild._id,
+      type: publicGuild.type,
+      privacy: publicGuild.privacy,
+      name: publicGuild.name,
+    });
   });
 
   it('should return challenges user has created', async () => {
@@ -40,8 +50,28 @@ describe('GET challenges/user', () => {
 
     let foundChallenge1 = _.find(challenges, { _id: challenge._id });
     expect(foundChallenge1).to.exist;
+    expect(foundChallenge1.leader).to.eql({
+      _id: publicGuild.leader._id,
+      profile: {name: user.profile.name},
+    });
+    expect(foundChallenge1.group).to.eql({
+      _id: publicGuild._id,
+      type: publicGuild.type,
+      privacy: publicGuild.privacy,
+      name: publicGuild.name,
+    });
     let foundChallenge2 = _.find(challenges, { _id: challenge2._id });
     expect(foundChallenge2).to.exist;
+    expect(foundChallenge2.leader).to.eql({
+      _id: publicGuild.leader._id,
+      profile: {name: user.profile.name},
+    });
+    expect(foundChallenge2.group).to.eql({
+      _id: publicGuild._id,
+      type: publicGuild.type,
+      privacy: publicGuild.privacy,
+      name: publicGuild.name,
+    });
   });
 
   it('should return challenges in user\'s group', async () => {
@@ -49,8 +79,28 @@ describe('GET challenges/user', () => {
 
     let foundChallenge1 = _.find(challenges, { _id: challenge._id });
     expect(foundChallenge1).to.exist;
+    expect(foundChallenge1.leader).to.eql({
+      _id: publicGuild.leader._id,
+      profile: {name: user.profile.name},
+    });
+    expect(foundChallenge1.group).to.eql({
+      _id: publicGuild._id,
+      type: publicGuild.type,
+      privacy: publicGuild.privacy,
+      name: publicGuild.name,
+    });
     let foundChallenge2 = _.find(challenges, { _id: challenge2._id });
     expect(foundChallenge2).to.exist;
+    expect(foundChallenge2.leader).to.eql({
+      _id: publicGuild.leader._id,
+      profile: {name: user.profile.name},
+    });
+    expect(foundChallenge2.group).to.eql({
+      _id: publicGuild._id,
+      type: publicGuild.type,
+      privacy: publicGuild.privacy,
+      name: publicGuild.name,
+    });
   });
 
   it('should not return challenges user doesn\'t have access to', async () => {
diff --git a/test/api/v3/integration/challenges/PUT-challenges_challengeId.test.js b/test/api/v3/integration/challenges/PUT-challenges_challengeId.test.js
index e916ab5b7a..33cc2e5166 100644
--- a/test/api/v3/integration/challenges/PUT-challenges_challengeId.test.js
+++ b/test/api/v3/integration/challenges/PUT-challenges_challengeId.test.js
@@ -50,7 +50,7 @@ describe('PUT /challenges/:challengeId', () => {
     let res = await user.put(`/challenges/${challenge._id}`, {
       // ignored
       prize: 33,
-      groupId: 'blabla',
+      group: 'blabla',
       memberCount: 33,
       tasksOrder: 'new order',
       official: true,
@@ -63,7 +63,7 @@ describe('PUT /challenges/:challengeId', () => {
     });
 
     expect(res.prize).to.equal(0);
-    expect(res.groupId).to.equal(privateGuild._id);
+    expect(res.group).to.equal(privateGuild._id);
     expect(res.memberCount).to.equal(2);
     expect(res.tasksOrder).not.to.equal('new order');
     expect(res.official).to.equal(false);
diff --git a/test/api/v3/integration/groups/GET-groups_id.test.js b/test/api/v3/integration/groups/GET-groups_id.test.js
index 9cc2fce766..2ecb53a33f 100644
--- a/test/api/v3/integration/groups/GET-groups_id.test.js
+++ b/test/api/v3/integration/groups/GET-groups_id.test.js
@@ -43,10 +43,6 @@ describe('GET /groups/:id', () => {
 
         expect(group.leader._id).to.eql(leader._id);
         expect(group.leader.profile.name).to.eql(leader.profile.name);
-        expect(group.leader.items).to.exist;
-        expect(group.leader.stats).to.exist;
-        expect(group.leader.achievements).to.exist;
-        expect(group.leader.contributor).to.exist;
       });
     });
   });
diff --git a/test/api/v3/integration/groups/POST-groups.test.js b/test/api/v3/integration/groups/POST-groups.test.js
index 8a64ef4bb5..8036d6b0d8 100644
--- a/test/api/v3/integration/groups/POST-groups.test.js
+++ b/test/api/v3/integration/groups/POST-groups.test.js
@@ -32,12 +32,17 @@ describe('POST /group', () => {
     });
 
     it('sets the group leader to the user who created the group', async () => {
-      await expect(
-        user.post('/groups', {
-          name: 'Test Public Guild',
-          type: 'guild',
-        })
-      ).to.eventually.have.property('leader', user._id);
+      let group = await user.post('/groups', {
+        name: 'Test Public Guild',
+        type: 'guild',
+      });
+
+      expect(group.leader).to.eql({
+        _id: user._id,
+        profile: {
+          name: user.profile.name,
+        },
+      });
     });
   });
 
@@ -86,6 +91,12 @@ describe('POST /group', () => {
         expect(publicGuild.type).to.equal(groupType);
         expect(publicGuild.memberCount).to.equal(1);
         expect(publicGuild.privacy).to.equal(groupPrivacy);
+        expect(publicGuild.leader).to.eql({
+          _id: user._id,
+          profile: {
+            name: user.profile.name,
+          },
+        });
       });
     });
 
@@ -106,6 +117,12 @@ describe('POST /group', () => {
         expect(privateGuild.type).to.equal(groupType);
         expect(privateGuild.memberCount).to.equal(1);
         expect(privateGuild.privacy).to.equal(groupPrivacy);
+        expect(privateGuild.leader).to.eql({
+          _id: user._id,
+          profile: {
+            name: user.profile.name,
+          },
+        });
       });
 
       it('deducts gems from user and adds them to guild bank', async () => {
@@ -138,6 +155,12 @@ describe('POST /group', () => {
       expect(party.name).to.equal(partyName);
       expect(party.type).to.equal(partyType);
       expect(party.memberCount).to.equal(1);
+      expect(party.leader).to.eql({
+        _id: user._id,
+        profile: {
+          name: user.profile.name,
+        },
+      });
     });
 
     it('does not require gems to create a party', async () => {
diff --git a/test/helpers/api-integration/v3/object-generators.js b/test/helpers/api-integration/v3/object-generators.js
index b7785e664f..57f6e2163b 100644
--- a/test/helpers/api-integration/v3/object-generators.js
+++ b/test/helpers/api-integration/v3/object-generators.js
@@ -113,7 +113,7 @@ export async function createAndPopulateGroup (settings = {}) {
 // optional details argument for the initial challenge creation and an
 // optional update argument which will update the challenge via the db
 export async function generateChallenge (challengeCreator, group, details = {}, update = {}) {
-  details.groupId = group._id;
+  details.group = group._id;
   details.name = details.name || 'a challenge';
   details.shortName = details.shortName || 'aChallenge';
   details.prize = details.prize || 0;
diff --git a/website/src/controllers/api-v3/challenges.js b/website/src/controllers/api-v3/challenges.js
index a75cc6cc58..7eccbcb9bf 100644
--- a/website/src/controllers/api-v3/challenges.js
+++ b/website/src/controllers/api-v3/challenges.js
@@ -2,7 +2,10 @@ import { authWithHeaders } from '../../middlewares/api-v3/auth';
 import _ from 'lodash';
 import cron from '../../middlewares/api-v3/cron';
 import { model as Challenge } from '../../models/challenge';
-import { model as Group } from '../../models/group';
+import {
+  model as Group,
+  basicFields as basicGroupFields,
+} from '../../models/group';
 import {
   model as User,
   nameFields,
@@ -35,12 +38,12 @@ api.createChallenge = {
   async handler (req, res) {
     let user = res.locals.user;
 
-    req.checkBody('groupId', res.t('groupIdRequired')).notEmpty();
+    req.checkBody('group', res.t('groupIdRequired')).notEmpty();
 
     let validationErrors = req.validationErrors();
     if (validationErrors) throw validationErrors;
 
-    let groupId = req.body.groupId;
+    let groupId = req.body.group;
     let prize = req.body.prize;
 
     let group = await Group.getGroup({user, groupId, fields: '-chat', mustBeMember: true});
@@ -92,6 +95,17 @@ api.createChallenge = {
     }), group.save()]);
 
     let savedChal = results[0];
+    // TODO Instead of populate we make a find call manually because of https://github.com/Automattic/mongoose/issues/3833
+    // await Q.ninvoke(savedChal, 'populate', ['leader', nameFields]); // doc.populate doesn't return a promise
+    let response = savedChal.toJSON();
+    response.leader = (await User.findById(response.leader).select(nameFields).exec()).toJSON({minimize: true});
+    response.group = {
+      _id: group._id,
+      name: group.name,
+      type: group.type,
+      privacy: group.privacy,
+    };
+
     await savedChal.syncToUser(user); // (it also saves the user)
     res.respond(201, savedChal);
   },
@@ -122,7 +136,7 @@ api.joinChallenge = {
     if (!challenge) throw new NotFound(res.t('challengeNotFound'));
     if (challenge.isMember(user)) throw new NotAuthorized(res.t('userAlreadyInChallenge'));
 
-    let group = await Group.getGroup({user, groupId: challenge.groupId, fields: '_id type privacy', optionalMembership: true});
+    let group = await Group.getGroup({user, groupId: challenge.group, fields: '_id type privacy', optionalMembership: true});
     if (!group || !challenge.hasAccess(user, group)) throw new NotFound(res.t('challengeNotFound'));
 
     challenge.memberCount += 1;
@@ -158,7 +172,7 @@ api.leaveChallenge = {
     let challenge = await Challenge.findOne({ _id: req.params.challengeId });
     if (!challenge) throw new NotFound(res.t('challengeNotFound'));
 
-    let group = await Group.getGroup({user, groupId: challenge.groupId, fields: '_id type privacy'});
+    let group = await Group.getGroup({user, groupId: challenge.group, fields: '_id type privacy'});
     if (!group || !challenge.canView(user, group)) throw new NotFound(res.t('challengeNotFound'));
 
     if (!challenge.isMember(user)) throw new NotAuthorized(res.t('challengeMemberNotFound'));
@@ -186,25 +200,32 @@ api.getUserChallenges = {
   async handler (req, res) {
     let user = res.locals.user;
 
-    let groups = user.guilds.slice(0); // slice is used to clone the array so we don't modify it directly
-    if (user.party._id) groups.push(user.party._id);
-    groups.push('habitrpg'); // tavern challenges
-
     let challenges = await Challenge.find({
       $or: [
         {_id: {$in: user.challenges}}, // Challenges where the user is participating
-        {groupId: {$in: groups}}, // Challenges in groups where I'm a member
+        {group: {$in: user.getGroups()}}, // Challenges in groups where I'm a member
         {leader: user._id}, // Challenges where I'm the leader
       ],
       _id: {$ne: '95533e05-1ff9-4e46-970b-d77219f199e9'}, // remove the Spread the Word Challenge for now, will revisit when we fix the closing-challenge bug TODO revisit
     })
     .sort('-official -timestamp')
-    // TODO populate
-    // .populate('group', '_id name type')
-    // .populate('leader', 'profile.name')
+    // .populate('group', basicGroupFields)
+    // .populate('leader', nameFields)
     .exec();
 
-    res.respond(200, challenges);
+    let resChals = challenges.map(challenge => challenge.toJSON());
+    // TODO Instead of populate we make a find call manually because of https://github.com/Automattic/mongoose/issues/3833
+    await Q.all(resChals.map((chal, index) => {
+      return Q.all([
+        User.findById(chal.leader).select(nameFields).exec(),
+        Group.findById(chal.group).select(basicGroupFields).exec(),
+      ]).then(populatedData => {
+        resChals[index].leader = populatedData[0].toJSON({minimize: true});
+        resChals[index].group = populatedData[1].toJSON({minimize: true});
+      });
+    }));
+
+    res.respond(200, resChals);
   },
 };
 
@@ -234,14 +255,20 @@ api.getGroupChallenges = {
     let group = await Group.getGroup({user, groupId});
     if (!group) throw new NotFound(res.t('groupNotFound'));
 
-    let challenges = await Challenge.find({groupId})
+    let challenges = await Challenge.find({group: groupId})
       .sort('-official -timestamp')
-      // TODO populate
-      // .populate('group', '_id name type')
-      // .populate('leader', 'profile.name')
+      // .populate('leader', nameFields) // Only populate the leader as the group is implicit
       .exec();
 
-    res.respond(200, challenges);
+    let resChals = challenges.map(challenge => challenge.toJSON());
+    // TODO Instead of populate we make a find call manually because of https://github.com/Automattic/mongoose/issues/3833
+    await Q.all(resChals.map((chal, index) => {
+      return User.findById(chal.leader).select(nameFields).exec().then(populatedLeader => {
+        resChals[index].leader = populatedLeader.toJSON({minimize: true});
+      });
+    }));
+
+    res.respond(200, resChals);
   },
 };
 
@@ -268,13 +295,21 @@ api.getChallenge = {
     let user = res.locals.user;
     let challengeId = req.params.challengeId;
 
-    let challenge = await Challenge.findById(challengeId).exec();
+    let challenge = await Challenge.findById(challengeId)
+      // .populate('leader', nameFields) // don't populate the group as we'll fetch it manually later
+      .exec();
     if (!challenge) throw new NotFound(res.t('challengeNotFound'));
 
-    let group = await Group.getGroup({user, groupId: challenge.groupId, fields: '_id type privacy', optionalMembership: true});
+    // Fetching basicGroupFields
+    let group = await Group.getGroup({user, groupId: challenge.group, fields: basicGroupFields, optionalMembership: true});
     if (!group || !challenge.canView(user, group)) throw new NotFound(res.t('challengeNotFound'));
 
-    res.respond(200, challenge);
+    let chalRes = challenge.toJSON();
+    chalRes.group = group.toJSON({minimize: true});
+    // TODO Instead of populate we make a find call manually because of https://github.com/Automattic/mongoose/issues/3833
+    chalRes.leader = (await User.findById(chalRes.leader).select(nameFields).exec()).toJSON({minimize: true});
+
+    res.respond(200, chalRes);
   },
 };
 
@@ -301,9 +336,9 @@ api.exportChallengeCsv = {
     let user = res.locals.user;
     let challengeId = req.params.challengeId;
 
-    let challenge = await Challenge.findById(challengeId).select('_id groupId leader tasksOrder').exec();
+    let challenge = await Challenge.findById(challengeId).select('_id group leader tasksOrder').exec();
     if (!challenge) throw new NotFound(res.t('challengeNotFound'));
-    let group = await Group.getGroup({user, groupId: challenge.groupId, fields: '_id type privacy', optionalMembership: true});
+    let group = await Group.getGroup({user, groupId: challenge.group, fields: '_id type privacy', optionalMembership: true});
     if (!group || !challenge.canView(user, group)) throw new NotFound(res.t('challengeNotFound'));
 
     // In v2 this used the aggregation framework to run some computation on MongoDB but then iterated through all
@@ -377,7 +412,7 @@ api.updateChallenge = {
     let challenge = await Challenge.findById(challengeId).exec();
     if (!challenge) throw new NotFound(res.t('challengeNotFound'));
 
-    let group = await Group.getGroup({user, groupId: challenge.groupId, fields: '_id name type privacy', optionalMembership: true});
+    let group = await Group.getGroup({user, groupId: challenge.group, fields: '_id name type privacy', optionalMembership: true});
     if (!group || !challenge.canView(user, group)) throw new NotFound(res.t('challengeNotFound'));
     if (!challenge.canModify(user)) throw new NotAuthorized(res.t('onlyLeaderUpdateChal'));
 
@@ -398,12 +433,12 @@ async function _closeChal (challenge, broken = {}) {
   await Challenge.remove({_id: challenge._id}).exec();
 
   // Refund the leader if the challenge is closed and the group not the tavern
-  if (challenge.groupId !== 'habitrpg' && brokenReason === 'CHALLENGE_DELETED') {
+  if (challenge.group !== 'habitrpg' && brokenReason === 'CHALLENGE_DELETED') {
     await User.update({_id: challenge.leader}, {$inc: {balance: challenge.prize / 4}}).exec();
   }
 
   // Update the challengeCount on the group
-  await Group.update({_id: challenge.groupId}, {$inc: {challengeCount: -1}}).exec();
+  await Group.update({_id: challenge.group}, {$inc: {challengeCount: -1}}).exec();
 
   // Award prize to winner and notify
   if (winner) {
diff --git a/website/src/controllers/api-v3/groups.js b/website/src/controllers/api-v3/groups.js
index b9b633c111..ff223bcef8 100644
--- a/website/src/controllers/api-v3/groups.js
+++ b/website/src/controllers/api-v3/groups.js
@@ -5,8 +5,12 @@ import cron from '../../middlewares/api-v3/cron';
 import {
   INVITES_LIMIT,
   model as Group,
+  basicFields as basicGroupFields,
 } from '../../models/group';
-import { model as User } from '../../models/user';
+import {
+  model as User,
+  nameFields,
+} from '../../models/user';
 import { model as EmailUnsubscription } from '../../models/emailUnsubscription';
 import {
   NotFound,
@@ -55,11 +59,14 @@ api.createGroup = {
 
     let results = await Q.all([user.save(), group.save()]);
     let savedGroup = results[1];
+    // TODO Instead of populate we make a find call manually because of https://github.com/Automattic/mongoose/issues/3833
+    // await Q.ninvoke(savedGroup, 'populate', ['leader', nameFields]); // doc.populate doesn't return a promise
+    let response = savedGroup.toJSON();
+    response.leader = (await User.findById(response.leader).select(nameFields).exec()).toJSON({minimize: true});
 
+    res.respond(201, response);
     firebase.updateGroupData(savedGroup);
     firebase.addUserToGroup(savedGroup._id, user._id);
-
-    return res.respond(201, savedGroup); // TODO populate
   },
 };
 
@@ -87,7 +94,7 @@ api.getGroups = {
 
     // TODO validate types are acceptable? probably not necessary
     let types = req.query.type.split(',');
-    let groupFields = 'name description memberCount balance';
+    let groupFields = basicGroupFields.concat('description memberCount balance');
     let sort = '-memberCount';
     let queries = [];
 
@@ -152,7 +159,7 @@ api.getGroup = {
     let validationErrors = req.validationErrors();
     if (validationErrors) throw validationErrors;
 
-    let group = await Group.getGroup({user, groupId: req.params.groupId, populateLeader: true});
+    let group = await Group.getGroup({user, groupId: req.params.groupId, populateLeader: false});
     if (!group) throw new NotFound(res.t('groupNotFound'));
 
     if (!user.contributor.admin) {
@@ -163,6 +170,8 @@ api.getGroup = {
       });
     }
 
+    // TODO Instead of populate we make a find call manually because of https://github.com/Automattic/mongoose/issues/3833
+    group.leader = (await User.findById(group.leader).select(nameFields).exec()).toJSON({minimize: true});
     res.respond(200, group);
   },
 };
diff --git a/website/src/controllers/api-v3/members.js b/website/src/controllers/api-v3/members.js
index 142926ed64..de2213d3b6 100644
--- a/website/src/controllers/api-v3/members.js
+++ b/website/src/controllers/api-v3/members.js
@@ -74,12 +74,12 @@ function _getMembersForItem (type) {
     let group;
 
     if (type === 'challenge-members') {
-      challenge = await Challenge.findById(challengeId).select('_id type leader groupId').exec();
+      challenge = await Challenge.findById(challengeId).select('_id type leader group').exec();
       if (!challenge) throw new NotFound(res.t('challengeNotFound'));
 
       // optionalMembership is set to true because even if you're not member of the group you may be able to access the challenge
       // for example if you've been booted from it, are the leader or a site admin
-      group = await Group.getGroup({user, groupId: challenge.groupId, fields: '_id type privacy', optionalMembership: true});
+      group = await Group.getGroup({user, groupId: challenge.group, fields: '_id type privacy', optionalMembership: true});
       if (!group || !challenge.canView(user, group)) throw new NotFound(res.t('challengeNotFound'));
     } else {
       group = await Group.getGroup({user, groupId, fields: '_id type'});
@@ -212,7 +212,7 @@ api.getChallengeMemberProgress = {
 
     // optionalMembership is set to true because even if you're not member of the group you may be able to access the challenge
     // for example if you've been booted from it, are the leader or a site admin
-    let group = await Group.getGroup({user, groupId: challenge.groupId, fields: '_id type privacy', optionalMembership: true});
+    let group = await Group.getGroup({user, groupId: challenge.group, fields: '_id type privacy', optionalMembership: true});
     if (!group || !challenge.canView(user, group)) throw new NotFound(res.t('challengeNotFound'));
     if (!challenge.isMember(member)) throw new NotFound(res.t('challengeMemberNotFound'));
 
diff --git a/website/src/controllers/api-v3/tasks.js b/website/src/controllers/api-v3/tasks.js
index df78ca3a4f..2b711a5a2a 100644
--- a/website/src/controllers/api-v3/tasks.js
+++ b/website/src/controllers/api-v3/tasks.js
@@ -216,9 +216,9 @@ api.getChallengeTasks = {
     let user = res.locals.user;
     let challengeId = req.params.challengeId;
 
-    let challenge = await Challenge.findOne({_id: challengeId}).select('groupId leader tasksOrder').exec();
+    let challenge = await Challenge.findOne({_id: challengeId}).select('group leader tasksOrder').exec();
     if (!challenge) throw new NotFound(res.t('challengeNotFound'));
-    let group = await Group.getGroup({user, groupId: challenge.groupId, fields: '_id type privacy', optionalMembership: true});
+    let group = await Group.getGroup({user, groupId: challenge.group, fields: '_id type privacy', optionalMembership: true});
     if (!group || !challenge.canView(user, group)) throw new NotFound(res.t('challengeNotFound'));
 
     await _getTasks(req, res, res.locals.user, challenge);
diff --git a/website/src/models/challenge.js b/website/src/models/challenge.js
index 62307f6d8e..b67e8b7832 100644
--- a/website/src/models/challenge.js
+++ b/website/src/models/challenge.js
@@ -20,7 +20,7 @@ let schema = new Schema({
     rewards: [{type: String, ref: 'Task'}],
   },
   leader: {type: String, ref: 'User', validate: [validator.isUUID, 'Invalid uuid.'], required: true},
-  groupId: {type: String, ref: 'Group', validate: [validator.isUUID, 'Invalid uuid.'], required: true},
+  group: {type: String, ref: 'Group', validate: [validator.isUUID, 'Invalid uuid.'], required: true},
   memberCount: {type: Number, default: 1},
   prize: {type: Number, default: 0, min: 0}, // TODO no update?
 });
@@ -31,7 +31,7 @@ schema.plugin(baseModel, {
 });
 
 // A list of additional fields that cannot be updated (but can be set on creation)
-let noUpdate = ['groupId', 'official', 'shortName', 'prize'];
+let noUpdate = ['group', 'official', 'shortName', 'prize'];
 schema.statics.sanitizeUpdate = function sanitizeUpdate (updateObj) {
   return this.sanitize(updateObj, noUpdate);
 };
@@ -49,10 +49,7 @@ schema.methods.canModify = function canModifyChallenge (user) {
 // Returns true if user has access to the challenge (can join)
 schema.methods.hasAccess = function hasAccessToChallenge (user, group) {
   if (group.type === 'guild' && group.privacy === 'public') return true;
-  let userGroups = user.guilds.slice(0); // clone user.guilds so we don't modify the original
-  if (user.party._id) userGroups.push(user.party._id);
-  userGroups.push('habitrpg'); // tavern
-  return userGroups.indexOf(this.groupId) !== -1;
+  return user.getGroups().indexOf(this.group) !== -1;
 };
 
 // Returns true if user can view the challenge
diff --git a/website/src/models/group.js b/website/src/models/group.js
index 1bbb0145a5..890662de4c 100644
--- a/website/src/models/group.js
+++ b/website/src/models/group.js
@@ -84,6 +84,9 @@ schema.statics.sanitizeUpdate = function sanitizeUpdate (updateObj) {
   return this.sanitize(updateObj, noUpdate);
 };
 
+// Basic fields to fetch for populating a group info
+export let basicFields = 'name type privacy';
+
 // TODO migration
 /**
  * Derby duplicated stuff. This is a temporary solution, once we're completely off derby we'll run an mongo migration
@@ -472,7 +475,7 @@ schema.methods.leave = async function leaveGroup (user, keep = 'keep-all') {
 
   let challenges = await Challenge.find({
     _id: {$in: user.challenges},
-    groupId: group._id,
+    group: group._id,
   });
 
   let challengesToRemoveUserFrom = challenges.map(chal => {
diff --git a/website/src/models/user.js b/website/src/models/user.js
index cc1ebccf54..31272dc874 100644
--- a/website/src/models/user.js
+++ b/website/src/models/user.js
@@ -654,6 +654,14 @@ schema.methods.isSubscribed = function isSubscribed () {
   return !!this.purchased.plan.customerId; // eslint-disable-line no-implicit-coercion
 };
 
+// Get an array of groups ids the user is member of
+schema.methods.getGroups = function getUserGroups () {
+  let userGroups = this.guilds.slice(0); // clone user.guilds so we don't modify the original
+  if (this.party._id) userGroups.push(this.party._id);
+  userGroups.push('habitrpg'); // tavern
+  return userGroups;
+};
+
 // Unlink challenges tasks (and the challenge itself) from user
 schema.methods.unlinkChallengeTasks = async function unlinkChallengeTasks (challengeId, keep) {
   let user = this;