A more general but no less potent payoff for discard effects is simply pressure
It taps to turn Plains into lands that produce colorless mana andthats it
It's an oldie but a goodie, and I love that it makes a creature brought back from the graveyard into a Zombie
Goblin Bombardment for infinite damage, Altar of Dementia for infinite mill, Ashnod's Altar for infinite mana, and so on
General enchantments, sagas, rooms, auras you can generalize and specialize as much as you want, and youll always have new tech to consider as new sets are released
As with other marketplaces like eBay and TCGPlayer, theres an excellent selection of sets available for purchase, but the biggest draw for many n this area is likely to be the easy access to different languages of cards