I love Kecleon and I'm so glad that GF threw him a bone in the form of Protean.
But... I thought Drain Punch and Iron Tail were Gen 4/5 moves, and thus incompatible with Protean. Or does Kecleon still get them as egg moves?
EDIT: I can confirm that Kecleon can NOT breed for Drain Punch, Iron Tail, and Knock Off-- these moves are illegal with Protean (as currently known).
It should also be noted that Protean Kecleon pretty much doesn't need Return; since it gets STAB on everything it doesn't need to run Normal-type moves that don't hit anything supereffectively, so you're better off just grabbing a coverage move even. Trick Room actually also sounds really good for Kecleon given how slow he is, but since he usually uses Priority I suppose it doesn't matter much.
It's too bad the bulk of Kecleon's powerful physical moves were gen 4-5 TMs or tutors, though. ;__; He would have loved that Iron Tail or Drain Punch. Looks like he's pretty much limited to PUP, the priority moves, and… uh… Rock Slide, I guess.
I wonder if Protean TrickBand would be any good.
Flygon is one Pokemon I've found PUP to be pretty good on (in-game, anyway, I'll test some Flygon sets on Showdown at some point). In-game I've been running Flygon with Assault Vest and P-up Punch and the extra bulk against special attackers helps him immensely in setting up with PUP. For Showdown, I'm thinking about some combination of P-up Punch and Defog or Roost, though he'll have coverage issues with his STABs in the current metagame… But eh it's worth a shot I suppose