Master Yi, Wuju Bladesman

Forestwalk
Highlander —If you control no other creatures, Master Yi gains first strike, vigilance, and haste.
Wuju Style —{x}{r}{r/g}: Master Yi gets +X/+0 and trample until your next end step.
Meditate —{x}{g/w}, {t}: Prevent the next X damage Master Yi would take. Then gain half of X life rounded up.

Whenever Master Yi deals combat damage, you may put one Alpha Strike counter on Master Yi. When Master Yi attacks, you may remove three Alpha Strike counters, if you do M