Only Return of the Wildspeaker can be cast at instant speed (outside of dinos cast with Progenitor's Icon), so you're vulnerable to losing your board and having nothing left to draw a new hand
Since theyre all part of Phyrexia, Phyrexian creatures usually relate to Phyrexias main themes: artifacts, oil counters, proliferate, +1/+1 counters, infect or toxic, and now incubate
That two energy when it ETBs and the card advantage you gain is a big factor to the call for this 2-drops ban
Out of the Tombs Out of the Tombs is a build-around that I could see being very fun, but itll require a Cube that gives you time to crank up eon counters while also facilitating decks that are competitive against the sort of engines that make a card like this worth playing
Sab-Sunen, Luxa Embodied One of the most powerful cards from the set and also one of the most enigmatic ones, Sab-Sunen, Luxa Embodied is a tough nut to crack
I'm not telling you to jam your college fund into buying a thousand copies of one of these cards