The Guide’s Purpose
Once you unlock a secret class, you can check its requirements and description in the pause menu under Secret Classes.
Secret Classes Menu
In this guide, I show the requirements for unlocking every Secret Class. Each class requires specific tower stats, so you need to build and upgrade your towers until they meet the required criteria.
Secret Classes
Below is a complete list of all 19 Secret Classes, including their required stats and special effects.
| Class Name | Stats Required | Class Description |
|---|---|---|
| Shady Doctor | Poison 30+ & Heal Aura 3+ | Enemies poisoned by this tower heal all towers within its aura for 0.25% of poison damage dealt (max 40 HP/s). |
| Purgatory | Burn Aura 3+ & Heal Aura 3+ | All enemies within your burn or healing aura can no longer heal. |
| Thorns | Armor 10+ & Max HP 500+ | Every hit this tower takes deals 10 damage back to the attacker. |
| Artillery | Range 14+ & Splash 5+ | This unit deals up to 100% more damage depending on the distance between it and the enemy. |
| Chain Lightning | Crit 175+ & Chain 3+ | Additional targets hit take full damage instead of 10% less damage. |
| Shatter | Stun 25+ & Knockback 5+ | Deals 250% extra damage to slowed enemies. |
| Dizzy | Multishot 4+ & Slow 125+ | Enemies hit briefly walk in a random direction and do not attack. Bosses and minibosses are immune. |
| Aurabot | Damage Aura 4+ & Atk Spd Aura 4+ | Increases the range of all auras on this tower by 66%. |
| Sniper | Armor Shred 10+ & Pierce 4+ | Deals 100% extra damage to elites, minibosses, and bosses. |
| Specialist | Chain 2+ & Multishot 2+ & Splash 2+ | Gains up to 100% faster attack speed depending on the number of alive enemies. |
| Immortal | Heal Aura 3+ & Armor 8+ & Max HP 300+ | Takes 66% less damage from minibosses and bosses. |
| Clapback | Knockback 5+ & Max HP 400+ | The first time each wave this tower falls to 50% HP, it knocks back all nearby non-boss enemies. |
| Ramping Toxicity | Attack Speed 4+ & Poison 30+ | Each time this tower attacks, its poison increases by 0.5 until the end of the wave. |
| Freezerburn | Burn Aura 3+ & Slow Aura 3+ | This tower’s burn aura deals 200% increased damage to slowed enemies. |
| Main Tank | Burn Aura 3+ & Max HP 450+ | This building redirects 80% of the damage taken by other buildings inside its burn aura to itself. Other Main Tanks are excluded. |
| Shredder | Armor Shred 25+ | Armor shred from this tower can push armor into negative values, increasing damage taken. |
| Support | Heal Aura 5+ & Armor Aura 5+ | No longer attacks or harvests. Its heal and armor auras are up to 150% stronger based on its damage or harvest amount (max at 100 damage / 10 harvest). |
| Heavy Armor | Armor 10+ & Armor Aura 5+ | Gains up to 150% additional max HP based on its total armor, including all bonuses (max at 50 armor). |
| Speculator | Crit 135+ & Harvest Amount 7+ | This building’s harvest can critically hit for bonus resources. |
| Weightlifter | Armor 10+ & Harvest Speed 1s or less | Each time this harvester successfully harvests, it gains 2 armor for the rest of the wave. |