Leshrac’s Rite [Classic Sixth Edition]

Enchant creature
Enchanted creature has swampwalk. (It can’t be blocked as long as defending player controls a Swamp.)

“Bind me to thee, my soul to thine. I am your servant and your slave. Blood for blood, flesh for flesh, Leshrac, my lord.”
—Lim-Dûl, the Necromancer