1-.-Can any one plz tell me what Pokemon learn 1 hit ko moves and what..

There is a lot of poke'mon that learn one hit KO moves but they all (one hit KO move) have terrible accuracy so their not that good anyway. An example would be Groudon, Kyogre, Articuno ect. But still (this is on your next question), You could get some good Pokemon like: (This was my party not including my starter) Machoke-subbmission,dynamic punch and vital throw. Pelliper- Fly, Protect. (I'm only giving you their good moves) Claydol- Secret Power, Hyper beam. Manetric- Thunder, Thunderbolt, Shock Wave. Groudon-Earthquake, Fire Blast, Fissure ( Yes I know it's a one hit KO. I never said never to have them just not to obsess on them). Now the levels: Claydol- Lvl 47, Pelliper- Lvl 30,
Manetric- Lvl 51, Machoke-Lvl 53, Groudon lvl 59 ( Also my starter was on lvl 96 and it was a Blaziken). If you can get a party to look something like that than you in good shape! But you should take along alot of revives hyper potions
And full restores just to be safe .

I beat the elite four with my 43 Swellow, 53 Sceptile ( starter) and kyogre in 54. Only kyogre died but I bought some revievs and full restores I know this was in sapphire but groundeon could probably be ok instead of kyogre