I've only noticed this on Nintendo switch. When vexes are summoned during a raid, they do not act normal. They constantly fly straight up and down in one spot (Can be annoying and hard to hit). I cannot confirm if this is the same for vexes in mansions. I will update this once I figure it out.
Edit: effects regular vex ai. Doesn't just happen during raids.
Steps to Reproduce:
1. Start a raid or summon an evoker
2. Wait for vexes to spawn
3. Once vexes have spawned their movement is broken (especially during raids).
Vexes will fly straight up and down. They won't move out of the same area very quickly but the rate in which they fly up and down can increase. They will be hard to hit as well.
The vexes should fly around like normal and target certain entities. They should go fly after players and go through walls as normal.