Heat Meater was a mechanic that is scrapped in the final game.

The purpose for this mechanic is that, the more enemies you kill, their behavior changed. You would gain alot of point when killing them, but lose alot of point when being hurted. They would also change color.

Here are the heat attack:

Cheeseslime swing a wooden bat

Forknight gain jetpack and rush foward

Swedish Monkey throw a harmful banana

Mini John perform a jumpkick

Pencer stand in one place and suddenly lunge toward

Flying Anchovy inflate themself like a pufferfish and drop down

Tribe Cheese throw an axe that travel in arc (used in final game)

U.F.Olive upon defeated would become an Olive Trooper (used in final game)

Bandito Chicken drop an explosive bone (used in final game)

Pineacool perform a breakdance

Spit Cheese spit out a bigger spikeball

Noise Goblin's arrow would home in the player

Pickle would duplicate

Noisey would hold their breath before bouncing around

Pizza Slug would pull out a gun shoot (used in final game)

Shrimp Thug would throw a knife (used in final game)

Ninja Slice would throw a series of punch that fire out projectile

Snowman slide much faster

Pizza Soldier pull out a pizza cutter and attack with it

Cardboard Tank would charge toward in order to flattening the player

Source: Pizza Tower Miraheze wiki