UPDATED:
See my latest post below.
Quick mock up of an icrpg enemy heart tracker. Print it on both side of an A4, laminate it, grab a thin red whiteboard marker and this is how to use it:
Perhaps cross out a dead foe. Make another foe, drawing a dividing line a bit further by however many hearts it has.
Full sheet:
Comments and suggestions welcome! I still haven’t tried it at the table…
https://drive.google.com/file/d/1GFDM4IS4bbe6rwmdvcOBL703ZhkX9fs1/view?usp=sharing