Enemies
From Dungeon Defenders 2 Wiki
Overview
In the Dungeon Defenders 2 you fight a large amount of monsters, varying in damage they deal, and damage that they resist.
Dungeon Defenders 2 currently has no boss fights.
Not a lot of information about the plot is available, as we are in pre-alpha, there is no story mode. The enemies you face in Dungeon Defenders 2 are the Old Ones' army from the original Dungeon Defenders. The Developers have said it is likely related to the "defeat" of the Old One in the first game.
When a map wave is generated, the drops/loot allocated to that wave is sorted out to all monsters in that wave. This means that having a sub core destroyed does not have any effect on item drop rates (with total XP and Gold also reduced).