At rare, it seems a bit wasted. It feels like an effect better off at uncommon. Especially with the amount of mana you need in limited to make Eldrazi viable, this is pretty disappointing. This isn’t a card I’d ever want to pick as a rare in Limited. If it was 5 or more lands to get the extra mana, it may be fine, but by requiring seven or more lands, it's just not going to be relevant until so late in the game. Yeah there's a lot of mana ramp available right now but it just seems to me that making it my seventh land doesn’t really feel like something I’d want to do.
Of course, we don't have Eldrazi Temple in Standard, so this is probably the next best thing. Then again, the Temple was just reprinted at uncommon in Modern Masters 2015, and while this is a bit less narrow, I’d prefer the classic. Were this at uncommon, I’d probably be nicer to it and feel it was fine as complementing a strategy. But rares should typically be build around cards for Limited - not utility that won’t do you much good most games until turn seven.
In Commander, I still like Temple of the False God much more. Yes it requires five or more lands to even be able to tap for mana, but that mana can be used for anything. Still, this Temple might still see play in “mono-brown” Commander decks; that is, decks that have colorless commanders that can’t play colored lands. It can still tap for a mana at any point, and in addition to Temple of the False God, it can be okay. Artifact heavy decks would probably be fine with it, as well.
This might still see Constructed play in an Eldrazi ramp deck, so it could prove me wrong and be somewhat useful. It does help you cast your Ugin the Spirit Dragon, after all. Still, it’s still a pretty underwhelming land and it makes me long for the two cards that it’s most like instead.
What do you all think of this card?