What about rolling the aura on a "minion" instead of a normal monster? They should have 1.5x HP to start with I think?
well the whole reason to take normal mobs is that they get TZ affixes, unlike minions/champs/uniques
so you find a cursed TZ game, find the mobs in the area you want, shard it and then go snag one from further away where they spawn as TZ, preferably in a P8 game
still not 100% sure whether the normal/minion/uniques get 1.0/1.5/2.0x or 2.0/2.0/2.0x life when they become a named unique bound demon, but it doesn't really matter much when its something like 2 million vs 4 million hp