While casting spells without spending mana is great, Nashi can burn you out really fast
If your playgroup loves Sol Ring, Swords to Plowshares, Path to Exile and the like, this might still be up your street
(If a permanent with a stun counter would become untapped, remove one from it instead.) III Diamond Dust Draw a card for each tapped creature your opponents control.
How to play it : Use Shift to land her early after a smaller Tink for immediate value
Marcy: This does certainly have 'win-more' potential and issues, and also costs 5 mana, which means that in a format like Standard, that's a point of the game where you should probably just be winning, but if there were some way to get this down earlier or cheated out, could be good