­Green Mana Battery + Island
Uh... I accidentally Blue Mana Battery?

Kinda surprised this is the first time I've hit an obvious recolour cycle. But ok, let's see what else we can do. How about a storage land; wait, that's Sand Silos. This space was pretty well mined out long long ago.

Fine. How about an artifact that literally builds up lands? That feels interesting. Make sure it taps to do it, so that there's that nice element of risk.

Obviously, a card like this would need to be in a landfall set; so lets make it so that you can add the lands a few at a time if you like rather than all at once as you normally would.

Add asdflavourtext and an appropriate image, and we're done. One robot sheep for your land exploratoray pleasures. Oh. Mana cost and rarity. Um; can this be a one-drop? I guess since it needs to tap to work, that would give you your first possible extra land on turn 3. So sure. Might become a 2-drop, but 1 seems fine at rare. An ucommon version of this would probably attach the land on ETB and/or sac to use instead of continually grabbing more - the deck-stripping potency of this is part of its appeal though. And also suggest a wondeful idea of gifting the opponent a couple, then blowing them up and their land-in-play to leave them manascrewed forever. But mainly the obvious flavour text.

I like it; looks more like a construct than golem though.