this is not the correct section , you should open reports on bug report section and not technical support section but i reply anyway
there is a minion found by excavating that works like that , it does not deal damage but steals healt , this means the “max healt” is reduced , so you can heal only to max and not get back to 30 hp.
It don’t consume armor by design , this to kill enemys with huge amount of armor.
That minion is too good , so right know is temporary nerfed from 4 mana to 6 mana ( even if cards shows 4 mana ) and in a future patch they change it to something less powerfull