Ulamog, the Ceaseless Hunger is no joke, but Battle for Zendikar wasnt exactly overflowing with tournament-viable Eldrazi
Unfortunately, its a little sparse on generic offerings, with most of its new printings tied to the knight creature type
Sythis, Harvest's Hand costs less mana, gains additional life, and is an enchantment itself
Unlike Ugin, Rally the Ancestors doesnt ask that you spend a bunch of cards to get to eight mana to cast it, aka the Modern Scapeshift issue where your one card combo is really one card and seven others to get to the point of casting it. Rally just asks that you play specific creatures in your deck and then cast them
There's also Gwenom, which is basically classic card Bolas' Citadel but in the command zone