Critical Attacks (attacking a mob while the player is falling) causes mobs to become immortal. See FTBTeam/FTB-Presents-Direwolf20-1.16#185 for more descriptions of the issue.

Version info:
MythicBotany-1.16.3-1.2.3
Minecraft 1.16.5
Forge: 36.0.14

Dependency Mod Versions (Issue does not occur with only these mods)
Botania-1.16.4-411
curios-forge-1.16.5-4.0.4.0
LibX-1.16.3-1.0.11
Patchouli-1.16.4-48

Debug Crash: https://gist.github.com/VT-14/f492e7d494cd7767dfd16f5127f0bfcc
latest.log: https://gist.github.com/VT-14/1402b4e950b5eaa37ebde39e49180ef5
debug.log: https://gist.github.com/VT-14/e0f95b2228ba3e393e24a2f06396bcbc