Summoner's Pact
.
InstantSearch your library for a green creature card, reveal it, put it into your hand, then shuffle.
At the beginning of your next upkeep, pay 
. If you don't, you lose the game.
Chippy
Mystery Booster 2 (MB2)
• #74Rulings
If Summoner's Pact is countered, the delayed triggered ability that threatens you with a game loss won't trigger at the beginning of your next upkeep.
(wotc • 2021-03-19)
Although originally printed with a characteristic-defining ability that defined its color, this card now has a color indicator. This color indicator can't be affected by text-changing effects (such as the one created by Crystal Spray), although color-changing effects can still overwrite it.
(wotc • 2013-06-07)
Rulings
If Summoner's Pact is countered, the delayed triggered ability that threatens you with a game loss won't trigger at the beginning of your next upkeep.
(wotc • 2021-03-19)
Although originally printed with a characteristic-defining ability that defined its color, this card now has a color indicator. This color indicator can't be affected by text-changing effects (such as the one created by Crystal Spray), although color-changing effects can still overwrite it.
(wotc • 2013-06-07)