If you have Mercenary, IB and WHC bots all in the same party each bot has an AoE shout ultimate that knocks enemies back with various added effects. However they all seem to have the same AI “trigger” that causes them to use the ult. I think it has something to do with the number of nearby enemies. The problem occurs when all 3 bots are located close together (such as if you run the improved AI mod and they stick close to the player. If you get into a situation that instantly triggers the AI like a bunch of rats climbing out of a spawn point, all 3 bots will pop their ults in the same nanosecond. This effectively wastes 2/3 ults because the enemies are already knocked down and further shouts will have no effect. I would consider this to be a bug because it’s definitely not desired behaviour and while human players might waste multiple ults by accident they wouldn’t deliberately do so.
In order to fix this you need to add a few “intensity” levels to the ult trigger. If one of the bots uses a shout the others should hold off for about 5-10 seconds unless the situation gets worse. If 1-2 ults are used then the threshold for using further ults should rise accordingly so that the third only comes in if it is actually needed.
This also applies to the ranger, battle wizard and unchained ults as those ults also apply AoE knockback. However the conditions that trigger the AI to use them seem to be different and they don’t have the same “hive mind” effect as the aforementioned trio that causes them to ult at the same time.