Thinking about going against Arlo’s team, I had a thought. What about putting Torterra in the second spot? It resists water (Gary’s waterfall) and triple resists electric (Magnezone). Might have considerable trouble against Crobat, though. The combination of Razor leaf, Frenzy Plant, and Earthquake can do a fair amount of damage to the other two.
Torterra has no utility against Scyther or any of the round 3 pokemon (Dragonite, Charizard, Scizor), so I guess this is a stretch, but it would totally own Magnezone. Garchomp might be a better choice, though.