I need a new strategy

[Mockingchu]

The Lush Jungle Trial is my enemy. Get your laughing out now...
Anyhow, the freaking Totem Lurantis and its ally Pokemon (either a super evil Castform, or a Trumbeak that was rock type moves to pwn my Flying Types) always wreck me. HEY! I said to get your laughing out earlier! Don't laugh at my problems...
So yeah, Totem Lurantis is basically Satan in my eyes. *sigh* My team is a Level 17 Stufful (I just caught it and it's adorable but SUPER weak), Level 27 Rockruff, Level 28 Fletchinder (with Fire Z-Crystal), and Level 29 Decidueye (with Normal Z-Crystal).
Here's how most of my battles go:
Lurantis uses X-Scissor. Fletchinder uses Flame Charge (raises speed). Lurantis calls Castform/Trumbeak (Trumbeak is worse because it has a Rock Type move that wrecks Fletchinder). Lurantis uses Synthesis. ME:
The past few battles, I've tried raising Fletchinder's speed so I can use Inferno Overdrive while Lurantis is at low health before Lurantis uses Synthesis. Last time, I managed to FINALLY defeat Lurantis by using Quick Attack, but Fletchinder had been my last Pokemon, and Trumbeak used Rock Balls to ruin my day.
I think I need a new strategy. I've been using the same one for a while. And insanity is doing the same thing over and over while expecting different results.
Any advice?

 

[Sciencewars]

Don't sweat it, that one was hard. Maybe pick up a Sandygast for the next island?

 

[Shocari]

Try grabbing a Magby from Wela Volcano Park and getting it up to Magmar. It should easily be able to take down Lurantis with Flame Burst, or even a Firium Z boosted one, while resisting Castform's Fire Weather Ball from Sunny Day. Just always focus the Totem when it's out, save the SOS spawn for later since it'll keep respawning and respawning while the Totem is alive, making KOing it virtually worthless until the Totem's out.

 

[seel129]

well magbey helps alot, also anything with a poison attack well help too. (also don't feel to bad, i was stuck on that fight too)