Now you might be thinking "But there are four extant species of hyena, what about the aardwolf?", and thats valid, but aardwolves are essentially harmless to adventurers, so lets leave them out of this.
It strikes me as odd that we have hyena headed humanoids in classic D&D but no actual hyenas. We can rectify that...
Hyena
by Cab Davidson
| Stat | Striped | Brown | Spotted |
| AC: | 7 | 6 | 6 |
| HD: | 3 | 4 | 5 |
| Movement Rate: | 180’(60’) | 150’(50’) | 120’(40’) |
| Attacks: | 1 bite | 1 bite | 1 bite |
| Damage: | 1d6 | 2d4 | 3d4 |
| Number Appearing: | 1 (1d3) | 1d4 (2d4) | 1d4 (5d10) |
| Save As: | F1 | F2 | F3 |
| Morale: | 8 | 9 | 10 |
| Treasure Type: | U | V | Vx4 |
| Intelligence: | 2 | 3 | 3 |
| Alginment: | Neutral | Neutral | Neutral |
| XP Value: | 45 | 100 | 250 |
Hyenas are powerful scavengers and predators with crushing bites allowing them to break through tough skin and break bones. There are three species of hyena common to grasslands and brushland in hot regions. While being similar in form to wolves, with shorter legs, larger heads and more obviously powerful bodies, they are only distantly related to wolves, being somewhat closer to great cats.
Striped hyenas are the smallest species. They are entirely nocturnal, and while capable of bursts of speed they prefer to run within their capabilities, exhausting prey before striking. They spend daylight hours in dens dug into the earth.
Brown hyenas form small family clans, and prefer scavenging (or chasing other predators off kills) to hunting. They will however take small prey, and they are always disruptive around human and demi-human encampments which they will always raid for food.
Spotted hyenas are the largest among extant hyena species, and form vast clans that can rival any other hunters of the savannah. They are shockingly efficient pack hunters, and a constant pest of livestock. They prefer to chase other predators from their kills to hunting, but are capable of taking down prey many times greater than themselves.