Aha, been trying to get this documented right for weeks now…
Talking about Yao’s Corruption trait. Other traits may have similar results but this is the one I know for sure.
If I end a battle by killing the last troop with this trait, a bunch of things can happen. Namely, the fight will slow down by a lot while its doing the remainder of the board animations, in a similar fashion to it slowing down when you’ve clicked on a troop card while the board is in motion.
What is less common is this - if there’s a significant cascade happening, the animations can carry over to the victory screen. I’ve got a screenshot - finally - of some mana effects happening.
I’ve not seen this barrier show up before though, or if I did I wasn’t looking. (Top-left corner.)
The barrier stuck around until I got back to the PVP menu.