Thanks for detailed reports and save-files.
>eels getting hurt by spikes,
Yes, this was caused by infinite loop of spikes and 'on damage: Melee' trigger of Eel. Loop is now broken when Eel accumulates enough spike damage to die.
This is because 'Force end turn' does so immediately, thus skipping 'Single use' effect. I swapped these effects to fix it.
Uploaded new point release with these fixes.