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Gem Farming Guide

Efficient methods to farm gems in Universal Tower Defense. Maximize your summons with smart resource management.

9 min readData checked: 2026-07-06
Data Source:Code examples use Likely Active records checked on 2026-07-06. Challenge rewards use Trello-backed drops checked on 2026-07-06; Story and Virtual Realm mode facts are Likely/Likely. Gem-source amounts and summon cost/pity data remain Mixed planning model assumptions until in-game evidence is recorded.

Gem Economy Overview

100 Gems
= 1 Summon
400 Pity
Legacy Mythic model
0.5%
Mythic model rate
Generous
Gems are easy to get

Use this as a planning model, not a confirmed current economy table. Current codes and challenge drops are source-checked separately above.

Source-Checked Redemption Codes

These are examples from the canonical codes dataset. See the full codes page for the complete current list and review status.

200kInterestedUtopia
Free rewards
Likely Active
PirateKing!
100 Trait Rerolls, 150,000 Universal Gems, 10,000 Gems, 100,000 Gold
Likely Active
3.0Part1.5!
50 Trait Rerolls, 50 Relic Rerolls, 5,000 Gems, 50,000 Gold
Likely Active
100kInterestedWanoP2!
100,000 Gold, 10,000 Gems, 50 Trait Rerolls, 75,000 Universal Gems
Likely Active

Codes can expire or change rewards. No code is marked confirmed active until official or in-game evidence is recorded.

Gem Sources Ranked

S

Story Mode

~400 gems per Act15-25 min

Legacy planning source: High difficulty gives best rewards. Story facts are Likely canonical mode data.

Requires: Stable Story clear team
S

Level Milestones

Varies by levelPassive

Legacy summon model tracks level milestones as a major gem/reroll source; exact rewards need in-game review.

Requires: Just play the game
S+

Redemption Codes

Varies by code1 min

4 source-checked examples are shown below; see the codes page for the full current list.

Requires: None
A

Virtual Realm Hard

1000 gems20-30 min

Virtual Realm is Likely canonical mode data; gem amount remains Mixed model context.

Requires: Strong Virtual Realm team
A

Achievements

50-500 eachVaries

Many easy achievements give good gems. Check regularly.

Requires: Various
A

Unit Index (Collection)

500 gems per new MythicN/A

Legacy summon model tracks this as first-time collection value; exact current reward needs review.

Requires: Pull new Mythics
B

Daily/Half-hour Challenges

Gems 500x to 1000x10-15 min

Challenge reward facts are Likely / likely; reroll record: Rerolls 100% 1x to 3x.

Requires: Decent team
B

Group Rewards

100+1 min

Hidden box near Play area. Join Roblox group + like game.

Requires: None
B

AFK Chamber

Based on best timePassive

Set and forget. Generates rewards based on your best clear times.

Requires: Good clear times

Story Mode Gem Farming

Standard Method (75%)

  • Safe and consistent
  • Works with any team
  • Good gem rewards

High-Difficulty Method

  • ~400 gems per Act in the legacy planning model
  • Requires a stable DPS and economy setup
  • Higher-difficulty reward assumptions need in-game review

Daily Gem Checklist

Clear Gold Shop
Buy priority Trait Rerolls and Fragments when affordable
High
Claim Daily Quests
Easy gems and materials
High
Run Half-hour Challenges
Rerolls 100% 1x to 3x
High
Check Level Milestones
Claim after leveling up
High
Check Achievements
Many give gems passively
Medium
Set AFK Chamber
Passive resource generation
Medium

Gold Shop (Ramen Guy)

Don't Forget the Gold Shop!

Located near the spawn point. Uses Gold (not gems) to buy valuable items.

  • • Trait Rerolls - Prioritize them when affordable
  • • Rainbow Fragments - Evolution materials
  • • Burning/Ocean Fragments - Hard to farm otherwise

Gold availability depends on your account stage; avoid spending in a way that blocks core upgrades.

Gem Spending Priority

1

Banner Summons

Pull for canonical units such as Berserker, Spade, Kriatu, and Virtual Idol when they fit your team

2

Speed Cart Copies

Speed Cart/Fastcart dupes are useful, but duplicate requirements remain planning-model assumptions

3

Mythic Duplicates

For Etherealization of your main carries

Common Mistakes

  • Skipping Gold Shop

    Rerolls are limited. Check the shop, then buy only what your account can afford.

  • Ignoring Level Milestones

    Thousands of gems sitting unclaimed. Check after every level.

  • Playing at 100% when struggling

    Use 75% difficulty until you have strong units. Failing wastes time.

  • Missing Group Rewards

    Hidden box near Play area. Easy free gems, often overlooked.

Gem Farming Progression

1

Day 1

Check current codes → Pull for Speed Cart/Fastcart plus early DPS → Start Story progression

2

Week 1

Claim Level Milestones → Clear Story on higher difficulty → Farm Half-hour Challenges

3

Endgame

Virtual Realm and Featured Challenge rewards should be planned from source-checked mode/drop records

Related Guides

UTD Beginner Guide
Getting started basics
Unit Upgrade Priority
What to spend gems on