Power Depot

A land that enters carrying a +1/+1 counter is the sort of oddity that only makes sense once you see what it is built to feed. Modular 1 means Power Depot enters with a counter, and when it dies (and in an artifact deck it will die, to Arcbound Ravager, to a sacrifice outlet, to anything hungry for permanents), that counter jumps to an artifact creature. So the manabase becomes a resource that pays out on its own destruction rather than sitting quietly adjacent to the plan. The two mana abilities complete the picture. One taps for colorless that goes anywhere; the other taps for one mana of any color, but shackled to casting artifact spells or activating artifact abilities. That leash on the five-color access is what keeps the fixing honest: rainbow mana is enormous, so binding it to the artifact subtheme means the land only smooths a deck already committed to that plan. It never quietly becomes a rainbow source for a control shell. What makes the design worth studying is how many jobs it stacks into a single tapped land: it fixes for the artifact plan, it stores a body's worth of stat on death, and it doubles as sacrifice fodder that refunds its counter instead of vanishing. The rate never looks explosive, but a land that Arcbound Ravager can eat and still leave value behind is a genuinely different manabase object.