Wreckage of the Past

Wreckage of the Past enters the battlefield tapped.
Basic Plains are also swamps.
{t}: Add {b} equal to half the plains target
opponent controls rounded down.
"I kept wondering what would annihilate your golden
heart? And so I found Tomura. Groomed him to hate
you. Watched you smile proudly as you beat your
masters' descendant." -All For One