Interesting concept, might be better as a permanent. It could make mono life stalls better, but the mechanic might need to change. Perhaps sacrifice 1 creature to gain X max HP where X = the number of your creatures. This would pair nicely with empathic bond and mitosis, because once you are set up, you can generate a creature each turn just to eat while maintaining a full board to heal with. This is a different idea, but might be more 'life friendly'.