Preston Garvey, Minuteman

Ramp built out of combat, which is a stranger place to source mana than it sounds. Most fixing enters on your main phase, taps for value, and stays put; here the mana engine assembles itself in the combat step, one Settlement Aura at a time, and does the work of turning ordinary lands into any-color sources without ever touching your color of choice in the deckbuilding. The untap trigger is where the two halves lock together. Because those Auras attach to lands, and because attacking untaps every enchanted permanent you control, each swing refunds the mana those Settlements produce: the lands untap, tap again for whatever you need, and the combat that would normally leave you tapped out instead leaves you flush. That is the design tension the card resolves. Combat is usually the phase where you spend resources and expose yourself; this turns the attack step into a mana ritual, letting you hold up interaction or dump into an end-of-combat spell on a board that has already committed to the swing. The friction is that the whole engine keys off attacking, so the payoff only arrives when the 4/4 is willing to walk into a blocker or a removal spell. It rewards a board wide enough to make combat safe rather than a single threat leaning on the trigger, which is a coherent, table-scaled way to build a mana engine out of aggression.