Between the counter distribution on ETB and the general benefits of being in green, we should have no trouble maintaining the largest creature
Fury of the Horde sees competitive metagame play in 1 format(s): Commander.
If you see her across the table, pack some life-gain hate, or youre in for a long night
If you can dig up a Spellskite to further protect Ertai it would probably be very helpful, along with more ways to create tokens for sacrifice (Bitterblossom)
If multiple creatures enter at the same time, evolve will trigger for each of them, and you'll perform each comparison separately
They have strong sizes to casting cost, a strong ability when they are on the battlefield, and when they die they turn into their Temple, which taps for their mana and then heads back with a tap at sorcery speed but with a harder to do activation