Naesala, the Overlord

Trample, vigilance
At the beginning of your upkeep, put X number
of +1/+1 counters on Naesala, where X is Naesala's
power.
Prevent all damage dealt to Naesala.
Opponents and permanents controlled by opponents lose protection.
If your life total is equal to or less than half your starting life total, Naesala gets +5/+0.