Battle frozen when killing an enemy and spawning a new one

Platform, device version and operating system: Steam/PC and Android

Screenshot or image:

Forum is not letting me post my screenshot

What you were expecting to happen, and what actually happened: This happened only twice total in the recent days, once on PC/Steam and once on my Android device (Pixel 6A). In both instances it seems like a new enemy was summoned after a enemy with that kind of skill died to spawn the new one. I could not take a screenshot with Android because the app was unresponsive and not letting me use the screenshot command.

How often does this happen? When did it begin happening? This has only happened very rarely but has destroyed Delve runs, once in a low-level City of Thieves run, and another time during the current Zaejin Faction Assault event.

Steps to make it happen again

Not sure how to reproduce it consistently, but I am basically killing the enemy party with a dragon, and the “summon a new troop upon death” skill procs for one of the troops, and the game froze.