DamageArea

As the name implies, this area can be used to damage or heal Awesomenauts, creeps or droids. It also has many other uses.

This area is primarily used in AI Station 205 for the flame machine. You may want to check AffectArea as they are a lot easier to use specially if you just want to deal damage.

Useful damage settings
There are tons of damage settings used by the game to inflict damage/heal/buff/cc/etc. Here is a list of many useful damage settings and their functionality.