The Pokemon Company International and Nintendo announced on September 1, 2016 that they are giving away a very unique Munchlax to people who purchase Pokemon Sun or Pokemon Moon on or before January 11, 2017. This Munchlax is said to evolve to a Snorlax that can pulverize opposing Pokemon.
source: wiggle wiggle break
This bonus Munchlax from the early purchase holds a special item. It is called Snorlium Z. After evolving Munchlax to Snorlax, Snorlax will be able to use a special Z-Move - the Pulverizing Pancake.
Aside from the special item, this exclusive Munchlax is holding, it will also know the move Hold Back. Hold Back is an attack move that will leave its opponent with 1 HP. It is perfect when you're on a Pokemon catching spree.
source: pokecommunity forums
The last but not the least gift from this Munchlax is its Happy Hour move. It is one of those moves it couldn't normally learn. This Happy Hour move when used during a trainer battle will give you double the reward money after the battle.
source: degrassi wiki
Munchlax is of a Normal type Pokemon. It evolves into a Snorlax. As a baby Snorlax, it is known to be a big eater. It can eat as much as it weigh per day. Sometimes, they hide foods under their hair, but often forget about it.