My Team for RM

[Grassmaster]

Slaking item: normal gem
nature: relaxed Ability: truant
move-set:
low sweep
*earthquake
aerial ace
giga impact (pp: 8)

reuniclus Item: leftovers
nature: jolly Ability: Magic guard
move-set:
pain split
skill swap
recover
focus blast

Zoroark (charizard) item: razor claw
nature: serious Ability: illusion
move-set:
focus blast
aerial ace
shadow claw
dig

swampert item: rindo berry
nature: hasty Ability: torrent
move-set:
muddy water
earthquake
dive
focus blast

serperior Item: big root
nature: impish Ability: overgrow
move-set:
giga drain
leaf blade
aerial ace
leech seed

charizard Item: charti berry
nature: lonely Ability: blaze
move-set:
flame burst
fire blast
fly
dragon claw

*placeholder

the entire purpose of reuniclus is support. skill swap with slaking then recover and pain split to heal damaged teammates.
i hope to replace this serperior with one with a contrary ability

please tell me any way i can make this better without having to change the whole thing