Mount Grimrock's most commonly-found enemy, Skeleton Warriors are reasonably tough, especially for the inexperienced prisoners thrown into the dungeon. Although reasonably slow compared to some creatures in Grimrock, they are aggressive and fierce foes, their tower shields in particular giving them added defense up-close. They can be encountered both alone and in groups of four.
Medium health, medium damage, medium attack speed, medium movement speed, immune to poison
Side and rear attacks
Legionary Spear, Legionary Shield
You'll find these guys everywhere from the end of Level 1 onward. Skeleton Warriors are deadly early on, and should not be underestimated, but later in the game become cannon fodder. They are resistant to melee attacks, but only from the front - try to hit them from the sides or back to maximize damage. Because they often travel in formations, try to use attacks that hit multiple enemies, especially offensive spells. Note that they will always drop Legionary Spears and Shields, which are useful for low-level parties and for holding down floor switches when solving certain puzzles. Whatever you do, don't use poison attacks against them, as they are completely immune.