Magic: The Gathering

Blood moon style would be cool.

Mechanically, it's the same thing, really, but yeah, thematics.

Create a "wastes" ability counter like flying counters and finality counters. The counter has a rules-based ability that says the card its on is a land (without the 'in addition to other types' line) and taps for colorless mana, and loses all abilities.

Then the ability can be messed with, via cards that mess with counters and blinking/return to hand effects, but none of those are that easy to do to a land, which is fine for a 6-mana creature I feel.