Overlord is an action adventure game wherein the player controls a large mob of gremlin-like monsters called "Minions". The player's task as the game's "overlord" is to overcome the 7 corrupt heroes to get back his lands and solidify his authority on the citizens.
There are four minion races in Overlord. Though they look exactly the same, the minion races differ in color. Brown minions can fight in close-ranged combats. Blue minions can resurrect other minions. Red minions can shoot fireballs toward the enemies. Green minions can filter poison. These minions appear in the game from various spawn points in the field. A life force must first be paid to get a minion. Life points are gained by killing enemies. Only 5 minions can be summoned at the game's start. The maximum number of minions that can re-spawned is fifty. Minions can also be sacrificed to restore the player's health and mana. Mana is used for unique abilities and magic.
Overlord features 2 gameplay modes - single player and multiplayer. A story campaign can be completed when finishing the single player mode. There are different multiplayer modes. "Slaughter" sets up 2 Overlords to fight each other. "Pillage" makes Overlords compete on who can plunder the most amount of gold within a given time limit. In "Survival", the Overlords team up to fight a large group of enemies.