Requires 3 Tributes to Normal Summon (cannot be Normal Set). This card's Normal Summon cannot be negated. When Normal Summoned, cards and effects cannot be activated. Once per turn, during the End Phase, if this card was Special Summoned: Send it to the Graveyard. This card gains 1000 ATK and DEF for each card in your hand. If a monster(s) is Normal or Special Summoned to your opponent's field in face-up Attack Position: That monster(s) loses 2000 ATK, then if its ATK has been reduced to 0 as a result, destroy it.
|Other||1 Year Anniversary Reward [UR]|
Getting the tribute fodders can be easy if you use tokens or Ra's Disciple, but it won't be good if you don't pair them with other cards that can take advantage of it. You will also need some protection spell/trap cards in order to tribute summon for the next turn, or use Double Summon instead, making it quite a heavy investment and can be bad if your opponent can counter it.
Special summoning Slifer will only make it stay until the end phase, but it can still be effective if you summon it during your opponent's turn before they summon monsters. It can also still be good if you want an extra attack during your turn if you can secure the win.
Draw cards for certain monster type/attributes like Wonder Wand, Cards of the Red Stone, or even Soul Transition can be good if your deck synergizes with them, but cards like Jar of Greed or Good Goblin Housekeeping can be used in almost all decks, and it can even work as a surprise attack increase for Slifer. Golden Bamboo can also be good if you can pair that up with cards like Maha Vailo or Mythical Beast Cerberus.
Since Slifer can destroy, or cripple your opponent's summoned monsters, people will often set their monsters to defend against an attack. You can use cards like Meteorain or Big Bang shot to inflict some piercing damage when attacking them, or you can simply go for direct attacks instead. You can use cards like Shadowslayer, Secret Pass to the Treasures, or Shooting Star Bow - Ceal. Gravity Axe - Grarl can also be helpful to keep them locked and prevent flip effects.