DD7

creatures available for keethrax DD7:
CaveBear
CaveFisher
CaveLion
CaveLizard
CaveTiger
Cobra
DireWolf
FireBeetle
FireLizard
GiantBat
GiantCentipede
GiantFrog
GiantLizard
GiantRaccoon
GiantRat
GiantSlug
GiantSpider
HugeBat
Hyena
Jackal
LargeSnake
LargeSpider
RabidDog
Rat  
Rattlesnake
SilverWolf
Tarantula
Viper
WildCat
Wolf

Assuming equal chances of creation (should be checked), you'll have to kill or deal with 1010 monsters, on average, before you get a giant slug corpse (I think this assumed food preservation 90+).

1 in 10 of these will be cats (101 cats, my oh my.)