Any non-basic land which comes under one of the two land types specified by your fetch land can be added to the battlefield
For example, it's missing obvious proliferate cards like Contagion Clasp and Contagion Engine, its support makes no sense (why have a single Counterspell in the deck
Considering the creature is threatening to halve all of your opponents life totals, however, there is little chance your opponents are going to let this go without putting up some resistence
Time will tell whether any of these cards go too far, but its exciting seeing Magic bravely experiment
Forcing opponents to sacrifice is excellent because it gets around effects like hexproof, shroud, and indestructible
I think this one is still flying somewhat under the radar