Sonic, The Blue Blur

Flash, haste, first strike Dash {u}{w}—You may cast this card for its Dash cost. If you do, it gains double strike, fights target creature an opponent controls, and is returned to your hand on your end step.
Whenever Sonic deals combat damage to a player or planeswalker, create an emerald token. Sonic, The Blue Blur gains +1/+1 for each emerald token you control. As long as you control 7 or more emerald tokens Sonic has indestructible.