Bosses

There are 5 different bosses in total that are found at the last level of each stage. Bosses appear every 20 waves on custom maps and appear no earlier than on wave 40, unless a boss tile is present.

Bosses take 100% damage from all towers except Gauss, but some exhibit damage mitigation. All bosses are immune to Sniper's Killshot, being stunned or snowballed and take 90% less damage from abilities.

Name	Icon	Description
Broot		"On this level you'll meet the first boss. It is slow, heavy and simple, but don't think it'll be easy to deal with him, so be prepared. Destroy it and I'll report to Ensor mainframe about your success to get access to the next stage of levels and towers. I was analyzing your progress and can say that there's a big chance of success. Can't wait to see what will be opened for us next!" Slow and heavy. When HP drops under 25%, it goes into rage and runs slower for 8 seconds. When in rage, regenerates its HP with 50% of damage taken.
Stakey		"New boss incoming! It is a representation of a blockchain, actually a chain of enemies. Data we need is stored in one first block, other blocks add layers of encryption and make it harder to crack the main block. Just try to drop those encryption layers before going for the main block. Good luck!" Can be defeated only by destroying its head. Each part of body remaining reduces the damage taken by the head.
Constructor		”You will meet something interesting in this level. I think you also want to get access to a new resource? (glitch text) Well, this isn’t the interesting thing I was talking about, something needs to be done about it. We need to defeat the next boss. His name is Constructor, and he can make new enemies himself. Try to kill him as early as possible- when his HP drops to 75%, 50%, and 25%, he creates large groups of enemies.” Very slow, becomes invulnerable and creates enemies each 5 seconds on first half of its path. Also creates groups of enemies when HP drops below 75%, 50% and 25%. Constructor is immediately invulnerable to all damage when it stops to create enemies.
Mobchain		The Mobchain boss will appear in a few waves. Remember - you need different towers to cope with it. Head is invulnerable to damage during first phase. After the body parts are first destroyed, the head can then begin to take damage, but new body parts replace the destroyed ones. Phase 2 parts each have their own displayed weakness. During phase 1, Mobchain takes reduced damage from bullets and explosions by 90% when health drops below 66%, and then only takes full damage from bullets and explosions after health drops below 33%. Invulnerable to all effects related to movement.
Metaphor		"Good job, now the most interesting part begins - the Metaphor." Disables any tower that is one tile range near it. Will also disable 3 of the strongest tower on the map at any range when its health reaches 75%, 50% and 25%. Can create smaller spiders with very high health, but also high damage vulnerability.