Lightning Runner 90/184 (Aether Revolt)

Double strike, haste Whenever this creature attacks, you get {E}{E} (two energy counters), then you may pay eight {E}. If you pay, untap all creatures you control, and after this phase, there is an additional combat phase.

NM - $2.20
LP - $1.80
MP - $1.40
HP - $1.00
DMG - $0.60