As Pelt Collector’s first ability resolves, if the entering creature’s power is no longer greater than Pelt Collector’s power, or if Pelt Collector’s power has been raised to greater than or equal to the power of the creature that died, Pelt Collector doesn’t get a +1/+1 counter. Notably, this means that if Pelt Collector is still a 1/1 creature and two 2/2 creatures die, it only gets one +1/+1 counter as the first triggered ability resolves, and it will be too big to get a counter as the second triggered ability resolves.