So I had a battle at the 'Rating Battle' and fought Mandibuzz and my Pokemon was Swampert. We were both holding Rocky Helmet and this is how the battle went:
Swampert move: Rock Slide, Mandibuzz move: Taunt
(Rock Slide was super effective as usual then)
Swampert move: Hammer Arm , Mandibuzz move: Roost
Swampert move:Rock Slide, Mandibuzz move :Foul Play
When I used it here it had a normal Damage it wasn't a " super effective" then
Swampert faint then my Aggron was next I used Stone Edge and it was also not "super effective"
so can someone explain?