Deck Devastation Virus

Trap
Foretell {g}
Sacrifice a creature with 4 or more toughness, then
target opponent reveals the top six cards of their
library. Put one creature with toughness 4 or less
revealed this way, or on their battlefield, into their
graveyard. If this was cast on an opponents turn,
then you may put up to three creatures into their
graveyard instead.(Put the other revealed on bottom.)