Your search for "Power Matrix 229" revealed the following:
Power Conduit (MRD) from Mirrodin, available at 401 Games Canada. Rarity: Uncommon Finish: Normal Artist: Todd Lockwood Card Text:T, Remove a counter from a permanent you control: Choose one — Put a charge counter on target artifact; or put a...
Power Matrix (MB2) from Mystery Booster 2, available at 401 Games Canada. Rarity: Rare Finish: Normal Artist: Alan Pollack Card Text:T: Target creature gets +1/+1 and gains flying, first strike, and trample until end of turn.
Power Matrix (Foil) (MB2) from Mystery Booster 2, available at 401 Games Canada. Rarity: Rare Finish: Foil Artist: Alan Pollack Card Text:T: Target creature gets +1/+1 and gains flying, first strike, and trample until end of turn.