What is the effect of ''Slifer the Sky Dragon''?

Answer 1

Slifer the Sky Dragon

Attribute: DIVINE

Type: Divine-Beast (along with "Effect" in some Video Games)

Level: 10

ATK: X000 ("?" in some video games)

DEF: X000 ("?" in some video games)

Actual Lore: The heavens twist and thunder roars, signaling the coming of this ancient creature and the dawn of true power.

In-Game Lore (from Yu-Gi-Oh! 5D's World Championship 2010: Reverse of Arcadia): You must Tribute 3 Monsters you control to Normal Summon this card. The Tribute Summon of this card cannot be negated. When this card is Normal Summoned, a Spell, Trap, or Effect Monster Card cannot be activated. This card cannot be targeted by the effects of a Spell, Trap, or Effect Monster. If this card is Special Summoned, it is sent to the Graveyard during the End Phase. The ATK and DEF of this card becomes the number of cards in your Hand x 1000. When your opponent Normal Summons or Flip Summons a monster(s) with 2000 DEF or less, destroy the Summoned monster(s).