I’m new to the forum so apologies if this has been posted in the wrong location.

The cave in spell from DK one seemed somewhat lacking but fitted in well with the subterranean theme of DK.

The spell itself needs no explanation but I have some suggestions for its functionality.

1) The cave in spell would have a 'countdown' and 'area of effect' (possibly varying depending upon the mana cost/gold). Once the countdown expires any dug out sections of earth would be filled in with fresh earth. This wouldn’t remove wall sections but could damage room tiles.
2) The activation of the spell would cause creatures within the area of effect to attempt to flee before the collapsing debris crushes them.
3) The close proximity to the overworld could be demonstrated by the occasional random hero spawn accompanying this spell?

Its simple enough but tactically it could be used by keepers to seal breaches or fill subterranean caverns/ end large battles by chasing off monsters/ or crush the minions of any opponent not paying enough attention.

The spells efficiency could easily be balanced by high cost and a reasonably long countdown timer.