I just had an issue with the same interaction, but from a different standpoint. My opponent forced a draw on me by endlessly spawning thopters, while I had an attacking Soul Warden with an equipped Shadow Spear and a level 2 Cleric Class on board (and a Doomskar in hand for good measures), so every thopter he spawned gave me 2 life and a +1/+1 counter on the Soul Warden to nullify the added thopter. I deserved that win.
I just had an issue with the same interaction, but from a different standpoint. My opponent forced a draw on me by endlessly spawning thopters, while I had an attacking Soul Warden with an equipped Shadow Spear and a level 2 Cleric Class on board (and a Doomskar in hand for good measures), so every thopter he spawned gave me 2 life and a +1/+1 counter on the Soul Warden to nullify the added thopter. I deserved that win.