New and inventive common lands are really hard to make. I came up with a bunch of designs, but most of them pushed into uncommon/rare range, and some were common ideas, but there was no way to make it go off simple enough so that it would work in this set/be balanced.

I figured this worked well, though, being fair in constructed and something to build around in limited. There's a cylce of uncommon lairs in the set, but they're of the variety of "play with as few of me as possible". I'm not sure if syncing these up are a good idea or a bad idea. It kind of bugs me that you can't get colored land on round one, if you plan to get colored mana out of this land by round 2. That's probably an appropriate compromise, though.

Changed up the mechanic so it now etbs, and always produces one color instead of colorless. It also used to add or to the mana pool, now it adds one of any when 'turned on'.

It kind of bugged me that drafters would need to draft 3 of these cards, with different names, minimum, to get value out of them. Now they can draft just two and hope... and maybe it's worth it if they are packing four colors main deck.

Seems pretty reasonable for common. I agree the changes are an improvement.

I like this version a lot better. It just felt bed before. Both versions really push multicolor, though.

Is it intentional that this combos with Treva's Ruins et al?

More accidental... but I'm aware it happens to combo with them. I made a cycle of Lairs in uncommon that are similar to the Planeshift Lairs. See also: (((Viashino Lair))). I don't want to link these up, really, since players won't be happy to cast this first turn and have a 'normal' Lair in their hand... it's a bit of a bombo. That being the case, if this asks for a land type, and there are two different land types in the set, the players that want those two land types to link up will call shenanigans... and I think those people would be more upset, and think I don't know what I'm doing.