Why doesn't anyone talk about the huge bug in version 3.1 – the AI completely ignores creatures that appear on the map as a result of the weekly creature spawn (scattered randomly). It simply avoids them, and if it can't avoid them, it stands still or even tries to jump over the portal. :)

I wonder, is this happening on scenario maps or on random maps? The thing is, I always play on random maps, and with patch 3.1, I've never encountered this. Maybe it's a bug specific to a particular map? Then it would be worth generating a few more for testing. And I don't think you can "cancel" the creatures: that's the game's policy – at the beginning of each week, neutral creatures appear on the map. They get in the way, interfere with caravans, but you can use them to train newly created heroes with zero experience.