Munchlax's Thick Fat raises resistance to Fire/Ice moves
Dratini's Marvel Scale raises resistance to physical moves
Magikarp's Swift Swim raises speed in rain
Golurk's Iron Fist raises power of punching moves.
If (which is 99%) i get it wrong, cna I request for a hint?
I don't know. That hint tells me that I have a chance at getting this one right.
This one might be stretch, but here goes: All of the pokemon in this set, by their final evolutionary form, learn a base 150 power move towards the end of their level-up set. These moves also have the consequence of the user not being able to retaliate. Gyarados and Dragonite learn Hyper Beam, though Dragonite still learns Hurricane afterwards. Snorlax learns Giga Impact. Golurk learns Focus Punch, which leaves it immobile if its struck beforehand.
@Armando Payne, early hints are always vague, mainly to keep the points system as fair as possible. Hint 1 did narrow it down though, whether or not you were thinking of it relating to the manga/TCG or not.