Powder Keg (Jakub Slemr) [World Championship Decks 1999] Battle for Zendikar Prerelease Promos you may put its +1/+1

you may put its +1/+1 counters on target artifact creature

Set: Limited Edition Alpha Type: Artifact Rare Cost: {1} Creatures with power 3 or greater don't untap during their controllers' untap steps

then reveals the top card of their library

Set: Friday Night Magic 2003 Type: Creature — Sliver Rare Cost: {1}{G} All Sliver creatures get +1/+1

Set: Onslaught Type: Creature — Wurm Rare Cost: {1}{G} When Tempting Wurm enters the battlefield

Powder Keg (Jakub Slemr) [World Championship Decks 1999] Battle for Zendikar Prerelease Promos you may put its +1/+1Set: World Championship Decks 1999 Type: Artifact Rarity: Rare Cost: {2} At the beginning of your upkeep, you may put a fuse counter on Powder Keg. {T}, Sacrifice Powder Keg: Destroy each artifact and creature with converted mana cost equal to the number of fuse counters on Powder Keg.