Let's see... I'll bet at least some of these behaviors have been mentioned, but if so, they bear repeating. Can't provide specific examples, unfortunately.
- Playing Spark/Ball Lightning when it can't possibly do any damage that turn.
- Overlaying its own shield/weapon, even during the same turn, with no good reason to do so. (Especially glaring when they use Enchant/Protect Artifact on a shield/weapon, then overlay it.)
- Stealing or destroying a colored pillar(s)/tower(s) when there is also a Quantum Pillar(s)/Tower(s) present.
- Not detonating Unstable Gas, even when it has the
quantum available and the opponent doesn't have a spell-reflecting shield up. (Oddly, Octane seems to be fine about this, but other AI's seem to forget sometimes...)