I do like the effect of the card.
But like many other said, it could create some powerful combo, mainly because the buffed creature still retain its ability. I am just in mono deck, you could have Armagio + Converge + Otyugh = 11
for a 1|28 Otyugh that can eat pretty much anything.
Maybe as a balancer, make it the target also loose its ability too? I know its a bit boring, but might work out better...