UTD Wiki
This page is a structured reference for Universal Tower Defense. It is intentionally “wiki-like”: short, scannable sections you can consult quickly while planning summons, team roles, and upgrades.
Summon rates
Baseline probabilities for planning Gems budgets and banner strategy.
Unit acquisition
Standard summons, special banners, quests, and event methods.
Systems
Practical notes on team roles, upgrades, and progression decisions.
Units overview
Summon rates + obtain methods + a searchable showcase list.
Questions (FAQ)
Quick answers for codes, summons, progression, and safety.
Resources
Checklists, safe links, and a navigation hub.
Summon rates
These values are a planning baseline. Actual banners may change rates or highlight specific units.
Common
80%
Rare
17%
Epic
2.5%
Mythic
0.4%
Secret
0.1%
Practical advice: treat summoning like a budgeted activity. Set a Gems limit before you start. If you miss your target, stop and rebuild your currency through play and code redemptions.
How to obtain units
Different units are tied to different systems. Use this section to choose the fastest method for your goal.
Standard Summons
Use Gems to summon units. Typical pricing: 50 Gems (1x), 450 Gems (10x).
Special Banners
Special banners increase odds for specific units. Some banners may require account level milestones (e.g., Level 10+).
Quests & Challenges
Complete quests and event challenges for unique units and materials. Some units are tied to limited-time activities.
Tip: if you are summoning for a specific unit, confirm whether it is currently on a featured banner. Many games rotate availability, and “random summoning” tends to waste Gems.
Team building
Strong teams cover roles instead of chasing only rarity. A practical team usually has early coverage, main DPS scaling, utility (slow/stun/debuff), and a flexible slot.
If you are leaking, you likely need early coverage or utility. If you are timing out late waves, you likely need more scaling DPS or better upgrade timing.
For recommended investments, use Tier List.
Upgrades & breakpoints
Upgrades are most valuable at breakpoints: when they prevent leaks, improve clear speed enough to keep up with wave scaling, or enable a new placement strategy.
To avoid “upgrade spam,” compare two paths using the calculator: damage vs attack speed vs crit. Choose the cheapest upgrade that fixes your current bottleneck.
Use Calculator for fast comparisons.
Use the wiki as a checklist
Redeem codes, plan summons, invest with a tier list, and validate upgrades with the calculator.