As long as The Aetherspark is attached to a creature, The Aetherspark can't be attacked and has "Whenever equipped creature deals combat damage during your turn, put that many loyalty counters on The Aetherspark."
[+1]: Attach The Aetherspark to up to one target creature you control. Put a +1/+1 counter on that creature.
NM-Mint - $18.30
Lightly Played - $16.50
Moderately Played - $14.70
Heavily Played - $12.90
Damaged - $9.20
NM-Mint Non English - $18.30
Lightly Played Non English - $16.50
Moderately Played Non English - $14.70
Heavily Played Non English - $12.90
Damaged Non English - $9.20
Foil Prices
NM-Mint Foil - $22.40
Lightly Played Foil - $20.20
Moderately Played Foil - $17.90
Heavily Played Foil - $15.70
Damaged Foil - $11.20
NM-Mint Foil Non English - $22.40
Lightly Played Foil Non English - $20.20
Moderately Played Foil Non English - $17.90
Heavily Played Foil Non English - $15.70
Damaged Foil Non English - $11.20