After knocking enemy heroes or creatures unconscious it is possible to store them to the Prison. They can be left to rot in the Prison or put in the Torture Chamber. If the player wishes to leave them to rot, eventually they will rise as Skeletons. The Torture Chamber can be used to convert enemy heroes or torture them for map information.
Most heroes are worth converting, but if money is a problem; then the Skeleton is free, has no upkeep, and is as strong as a Goblin!
If your Torture Chamber is full and there are still heroes in the prison you want to have converted later, make sure to heal them using the heal spell.
In Dungeon Keeper 2, the amount of skeletons you can have in your undead legion depends on the size of your Prison; and since prison tiles have a moderate cost, it may be more worth while to use skeletons as cannon fodder in a army in some cases, not training them at all, and replenishing them with the freshly killed creatures as they die off. However, no matter the creature you kill in your Prison, you will not spawn new Skeletons if your skeleton count is maxed.
Creatures often have money on them and any money that a creature has will be dropped on the prison floor when it dies. This allows you to make some cash on the side by warmongering and taking prisoners. Beware though, creatures in the prison may pick up the newly dropped gold before you do. This won't be a problem if you are not planning to leave any prisoners alive. You may also want to have separate prisons for those you are planning to convert so they don't take the gold and leave when converted.
In Dungeon Keeper, only humanoid creatures can rise as Skeletons. If a creature has the Heal ability, it is unlikely to lose enough health by starving to die. The Keeper must first enable the imprison mode; otherwise enemies will be killed instead of stunned.
| ||Barracks / Bridge / Dungeon Heart / Graveyard / Guard Post / Hatchery / Lair / Library / Portal / Prison / Scavenger Room / Temple / Torture Chamber / Training Room / Treasure Room / Workshop|
| ||Casino / Combat Pit / Dungeon Heart / Graveyard / Guard Room / Hatchery / Hero Gate / Lair / Library / Mercenary Portal / Portal / Prison / Stone Bridge / Torture Chamber / Training Room / Treasury / Unholy Temple / Wooden Bridge / Workshop|
| ||Dragon Chamber / Infirmary / Kitchen / Crypt / Hive / Tomb / Summoning Chamber / Parlour|