KeeperRL Alpha 27 is out! This is another big gameplay update, introducing many improvements in playability and AI. You can now build your dungeons across multiple Z-levels, and digging downwards gives you access to extra resources, enemies and other surprises. Check below for the full change log. I'd like to thank everyone involved in crash testing this patch, sending bug reports and suggestions. Your help was invaluable!
If you would like to continue your saved game from Alpha 26, you can opt-in into the "Alpha 26 save compatibility" BETA branch under the game's properties in Library. Make sure to opt-out of the branch to go back to Alpha 27 when you're done!

Gameplay

• Z-levels!
• Items can be upgraded using glyphs.
• New random location: temples.
• New random location: ruins.
• Dragon AI learns how to breathe fire.
• Added leisure zone, where minions go when idle.
• Throwing items, firing ranged weapons and casting ranged spells have free instead of directional aim.
• AI tries to create formations when fighting in open areas.
• Healers and archer AI try to avoid melee combat.
• Healers make more effort to heal wounded allies.
• Tree spirits can be set on fire, and will actively seek out water to put it out.
• Added "entertainer" and "bad breath" immigrant traits, which influence minion morale.
• Increased spell and ranged max training of adventurers.
• Traveling between sites is restricted during combat and when poisoned.
• Creature AI knows how to use all resistance and vulnerability potions. (quaffing and throwing)
• Insane minions of retired keepers won't be used in raids.
• Minions won't go to sleep if they're poisoned.
• Added healing starting spell to white knight keepers.
• Creatures teleported by the throne get woken up.
• Insane minions won't attack the keeper.
• Insane immigrants get much higher damage bonuses.
• Knights, dragons and dwarves in the main dwarf villain are much stronger.
• Legendary minions are much stronger.
• Added rat people
• Adamantium golems are removed from the top level and exist only deep underground.
• Prisoners are no longer granted poison resistance.
• Combat experience bonus is reduced to the current level of given training type instead of the max level.
• Lizardmen are hostile to lawful adventurers.
• Added a basic wooden shield.
• AI won't enter tiles adjacent to fire when pathfinding to avoid fire damage.
• Corpses decrease morale instead of emitting poison gas.
• Switching between real-time and turn-based modes doesn't advance the game clock.
• Minions with night vision won't equip torches.
• Immigrants can come with extra wings or heads, the latter allowing equipping multiple helmets and amulets.
• Hydra has 7 heads which need to be cut off to kill it.
• The demon villain top level is a ruined castle.
• AI will try to go indoors at night.

Mods

• Mods can be switched in settings.
• Mineral patch numbers can be modded (per given z-level depth).
• Creatures and their inventories can be modded. New creatures can be added and used in immigration and as player characters.
• NegateRequirement immigrant requirement which lets you require that a requirement is not fulfilled.

Interface

• Improved character creation menu.
• Darkness and night is rendered directly on sprites to avoid ugly graphical glitches with lighting.
• When the player is killed, the notification is displayed below the center of the map so it doesn't obscure the view of what happened.
• Improved button visuals.
• Improved the lava animation.
• Added succubi lovemaking animation.
• Direct spell attacks have a magic animation.
• Immigrant legendary crafting skill is displayed explicitly.

Fixes

• Multiple optimizations.
• Reduced RAM usage per level, to accommodate Z-levels.
• Fixed worker AI getting stuck when idle.
• Control mode sidebar scrolling includes team member list. Fix
• Fixed eating task AI to not get stuck.
• Increased server connection timeouts.
• Fixed doppelganger consumption menu.
• Fixed issues with clicking on the game speed dialog.
• Keeper level button is not highlighted if there is nothing more to research
• Fixed bug in calculating visibility which showed itself in wrongly lit tiles after a forest fire.
• Fixed spell icon tooltips in control mode.
• Fixed AI crash when killing enemy using a projectile.
• Fixed a bug where a minion paces back and forth between two pigsties.
• Fixed UI buttons accuracy.
• Fixed AI issue with workers trying to drop items on inaccessible storage tiles.
• Fixed giant spider AI.
• Equipment storage located outside of territory is taken into account when assigning items.
• Goats are not treated as food.