The List

Ghost-Lit Stalker

{4}{B}, {T}: Target player discards two cards. Activate only as a sorcery.
Channel — {5}{B}{B}, Discard Ghost-Lit Stalker: Target player discards four cards. Activate only as a sorcery.

Duel Decks Anthology: Garruk vs. Liliana

{4}{B}, {T}: Target player discards two cards. Activate this ability only any time you could cast a sorcery.
Channel — {5}{B}{B}, Discard Ghost-Lit Stalker: Target player discards four cards. Activate this ability only any time you could cast a sorcery.

Duel Decks: Garruk vs. Liliana

Saviors of Kamigawa

{4}{B}, {T}: Target player discards two cards. Play this ability only any time you could play a sorcery.
Channel {5}{B}{B}, Discard Ghost-Lit Stalker: Target player discards four cards. Play this ability only any time you could play a sorcery.