As Luck Would Have It 
Enchantment
Hexproof Whenever you roll a die, put a number of luck counters on this enchantment equal to the result. Then if there are 100 or more luck counters on this enchantment, you win the game. (Count both rolls if you reroll a die.)
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyNOT LEGALvintageNOT LEGALcommanderNOT LEGAL