I really like the idea of monsters banding together for a mutual purpose, but not at the cost of immersion. Some monsters will look silly if they band with others.. like natural enemies.
Very basic examples.
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Dog meets Cat, cat submits to dog because dog has higher int.
Id rathe see...
Dog meets Cat, cat flees from dog but fails to escape.
Bye.
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Anyway, I'm sure you've thought of this [natural enemies]
Again poor example, my dog gets along with my cat great. But in the wild things arn't so tame. =-)
Lizards Hate Insects - Like Fish - Fear Undead
Insects Hate Fish - Like Undead - Fear Lizards
Undead Hate Mammals - Like Insect - Fear Plants
Plants Hate Lizard - Like Mammals - Fear Fish
Mammas Hate Undead - Like Magical - Fear Insects
Fish Hate Insects - Like Lizards - Mammals
Deamons Hate Angelic - Like Evil - Fear Nothing/Dragons
Angelic Hate Deamons - Like Good - Fear Nothing/Dragons
Dragons Hate All - Like None - Fears Nothing/Brad
Likes, Hates, Fears, Likes ++, Hates ++, Neutral 50%
Hates ++ = Engages enemy and ignores anything it hates/likes less than ++
Likes++ Engages for attach and ignores anyting it hates/likes less than ++
Fear overides all and books.
Neutral either fights or attaches