Using a shorthand to describe how creatures do things, specifically hunting or fighting, helps you run those creatures consistently which, in turn, allows players to learn behaviors and react to them. Here some rough categories that you can apply.
Ambush attackers
- Attack quickly from concealed positions.
Brute force attackers
- Attack a target with overwhelming ferocity and force.
Pack attackers
- Coordinated attack with multiple individuals.
Scavengers
- Attack already incapacitated or weakened targets.
Swarm attackers
- Uncoordinated attack with many individuals that sacrifice those individuals for effectiveness.
Trapsmiths
- Construct a trap that incapacitates or renders targets vulnerable to attack.
Venomous attackers
- Use a poisonous attack to down or incapacitate targets.
Choose suitable behaviors
Notice that I didn't construct this as a table. First, it's got an odd number of entries, which makes that tricky, but also because the behaviors should suit the strengths and abilities of the creature. The behavior a creature uses should be optimal to its capabilities. Study the creature-- what it does well-- and pick a behavior that matches up.
Mix and match behaviors!
Some creatures may use a single strategy while others may use multiple. Spiders, for example: some are venomous trapsmiths, others are non-venomous ambush attackers, etc.
Think about how behaviors interact with the environment
When thinking up a creature's lair, think about its behaviors. The behaviors a creature exhibits should be viable, optimal even, for the environment that the creature lives in.
Don't be too strict and have fun!
Finally, use behaviors as general guidelines but feel free to depart from them when it feels appropriate. They're meant to help not hinder your fun running games!
