(Create an Incubator token with three +1/+1 counters on it and ": Transform this token." It transforms into a 0/0 Phyrexian artifact creature.) Whenever a Phyrexian you control dies, surveil 1
Most notably, perhaps, it represented Magics first block (or one large set with two related smaller sets following it), which dominated the design and play of Magic for over 20 years
I would think Breakthrough is better because of the double use and negation during your turn, but I don't know
Countdown to endure 20 turns, more certainty than Exo who accelerates the draw
And knowing those exceptions in Limited can be an advantage that shouldnt be dismissed
Creature - Demon Phyrexian Color tag templates(None) Blade of the Bloodchief Whenever a creature dies, put a +1/+1 counter on equipped creature