You can spawn an Abbadon and use the wtf mode. This means his ultimate does not have a cooldown, which makes him nearly invincible. Except you are able to nuke him down to zero without bringing him under 400HP.
But this have a downside: his ultimate removes any negative buff. If you need a specific negative buff (ethereral blade, orchid, hex) for your combo, you have to stay with the tanky centaur.