Twas their numbers alone.
The deva could, on average, deal enough damage to kill a zombie with a single attack. And he had 2.
But unfortunately most of the time the zombie survived with 1-5 hp left.
And on those turns where he did kill 2. The fact there was 12 of them meant they were instantly replaced.
(By this point the necromancer ran away, scared for his life).
And with the deva hitting himself a few time. And the fact the zombies had a 25% hit rate with an average of 4 damage. And 8 could attack at once. The deva was killed. But on 3 zombies remained. Their hp was "1, 3, 1"
