I wouldnt even be shocked if the Commander Rules Committee allows Un- cards to be played on a more or less permanent basis
Open Hostility goes the other direction, with a a massive nine lands that are currently worth at least $1
If the active player casts a spell that has retrace, that player may cast that card again after it resolves, before another player can remove the card from the graveyard
It taps for green like a simple Forest would, but its channel ability makes it a main-deck answer to artifacts, enchantments, and nonbasic landsall at instant speed
The Reality Chip + Sensei's Divining Top + Cost Reducer Similar to the previous combo, using The Reality Chip, Sensei's Divining Top, and Foundry Inspector on the battlefield, you can tap the Top to draw a card and place it back on top of your library, then recast it from the top for free due to Foundry Inspector