Wall of Shards 23 (Coldsnap)

Defender, flying Cumulative upkeep—An opponent gains 1 life. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

NM - $12.20
LP - $9.80
MP - $7.40
HP - $4.90
DMG - $2.50