Level 13 (Diablo I)

Level 13 is the first Hell-style level in the original Diablo. The player(s) reaches Level 13 after from a stairway in Level 12. Somewhere in Level 13 there is a stairway to Level 14.

Upon entering Level 13, the character mentions, "I must be getting close".

Overall, this level represents a clear step up in difficulty. From this level Animals are reduced to very low numbers.

Accesses

 * Level 12
 * Tristram (a shortcut (a stairway) can be found on this level that leads straight back to town)
 * Level 14

Quests
If available, the following quest can be done or initiated in Level 13:
 * By reading Steel Tome (which is located somewhere on this level), a quest called Warlord of Blood starts; the completion of this quest will grant the passage to a stairway leading to Level 14 (which in game without this quest can be accessed like any level before this).

Bestiary
The following monsters can be found in Level 13:
 * Lava Maw
 * Storm Lord
 * Maelstorm
 * Guardian
 * Vortex Lord
 * Balrog
 * Cave Viper
 * Fire Drake
 * Gold Viper
 * Black Knight
 * Doom Guard
 * Blood Knight
 * Succubus
 * Snow Witch
 * Counselor

Unique Monsters

 * Doomcloud (Maelstorm)
 * Gorefeast (Vortex Lord)
 * Blackskull (Balrog)
 * Rustweaver (Doom Guard)
 * Warlord of Blood (Steel Lord/Quest)
 * Witchmoon (Snow Witch)