I've gotten past Lance, now struggling with champion.

What changes can I make to my team? I lead with Serperior so that the champion will immediately switch into eternus since it has toxic wave. Then I'm able to get two dragon pulses off but Serperior dies.

Then I switch into dragapult which gets the kill.

If he switches into miradon I use u turn to switch to mimikyu to use play rough, die then back to dragapult to finish off

But sometimes he switches into Yveltal and I will u turn which results in dragapult going to focus sash, then switch in weaville to take down the Yveltal

After I kill either of these he brings out metagross. I let weaville die so I can get dondozo in for free and try to earthquake but he ends up dying.

If I am able to take out metagross then he brings in phermosa and I try to rock tomb with kommo o to slow it down and weaken it enough so dragapult can get it.

The best I've done though is taking down either Eternus, Yveltal, and miradon. Or Eternus, Yvetal, and metagross.

Haven't even seen the ditto

Serperior @ Choice Scarf

Ability: Contrary

-Leaf Storm

-Dragon Pulse

-Glare

-Gastro Acid

Dondozo @ Leftovers

Ability: Unaware

-Ice Fang

-Body Slam

-Heavy Slam

-Earthquake

Kommo-o @ Mental Herb

Ability: Bulletproof

-Clangorous Soul

-Dragon Dance

-Rock Tomb 

-Drain Punch

Dragapult @ Focus Sash

Ability: Clear Body

-Shadow Ball

-Dragon Darts

-U turn

-Flamethrower

Mimikyu @ Life Orb

Ability: Disguise

-Destiny Bond 

-Play Rough

-Shadow Sneak

-Drain Punch

Weaville @Muscle Band 

Ability: Pressure 

-Triple Axel

-Ice Shard

-Low kick 

-Knock off