30th Anniversary Edition

Cockatrice

Flying
Whenever Cockatrice blocks or becomes blocked by a non-Wall creature, destroy that creature at end of combat.

Time Spiral Timeshifted

Fifth Edition

Flying
If Cockatrice blocks or is blocked by any non-Wall creature, destroy that creature at end of combat.

Fourth Edition Foreign Black Border

Fourth Edition

Flying
At the end of combat, destroy all non-wall creatures blocking or blocked by Cockatrice.

Summer Magic / Edgar

Foreign Black Border

Revised Edition

Flying
Any non-wall creature blocking Cockatrice is destroyed, as is any creature blocked by Cockatrice. Creatures destroyed in this way deal their damage before dying.