Graveyards are special areas where killed enemies come back to fight again as undead warriors. Only appearing in The Wastes and The Dark Tower, they can be a serious thorn in the player's side if not countered with the right defenses. Skeletons and Skeleton Knights from the Graveyard give gold, 2 (3 on Steam) and 10 respectively.
The graveyard itself is filled with old tombstones and is surrounded by a large fence. Reanimated enemies will rise up from the ground, before walking out onto the path.
A humanoid enemy, when killed, will either turn into a Skeleton or a Skeleton Knight, based on their maximum health: enemies with less than 300 health turn into a Skeleton, and enemies with 300 or more health turn into a Skeleton Knight. Beasts, flying enemies, and enemies polymorphed by Sorcerer Mages do not become skeletons.
Artillery towers are recommended to guard graveyards: the hordes that pour out of it can quickly become uncontrollable if otherwise. A 500mm Big Bertha or a Tesla x104's Overcharge can kill masses of skeletons in one shot.
If artillery towers are not available (in the Iron Challenges), stave off the skeletons with Barracks. The best strategy is to use Paladins, as they can heal themselves and their Holy Strike ability does area damage.
Another strategy is to use the Rangers Hideout, with Wrath of the Forest fully upgraded. The vines will constrict on the Skeletons, practically a 1 Hit K.O. for any entangled Skeleton. However, if Poison Arrows are upgraded, the Rangers will ignore the skeletons when other enemies are present, as skeletons are immune to poison and take second priority. Be cautious!