Use a Pokeflute to wake it up and then u can catch it or run away from it!
To get past snorlax on heartgold you need to get the power back on then go to the Kanto raido tower and get the radio get up graded by the man with the hat then go to snorlax and play the pokeflute on the pokegear by moving the circle to the top.When you battle snorlax kill him or catch him.
The PokeFlute is used to awaken Snorlax.
Pikachu Lapras Charizard Venasuar Blastoise Snorlax
Pikachu Lapras Snorlax
Route 11 - it should be obvious exactly where...
Pikachu, Charizard, Blastoise, Venusaur, Snorlax, Lapras.
Snorlax does not learn hypnosis.
get the pokeflute.
If you catch a Munchlax or Snorlax, they will have one. Otherwise, you can't get one.
Give it a full incense and breed it to get a Munchlax egg.
I forgot the levels but here are the Pokemon Pikachu Blastoise Snorlax Lapras Charizard Venusaur
Get the flute