I suppose this is a possible battle to win, it'll just be pretty difficult.
I just did the calculations. Assuming all our chips hit for full damage and swords and rageclaws get one hit, we'll do about 3480 damage (including elemental damage). Of course, I'd round that down to 3000 at least, accounting for misses and converted heals.
That means 40% of our damage on Riccio should come from sigs, busters, and tactics.
If the boomerangs hit twice with the 40% metal technique, that's another 360 for 3360. If the elecreel-on-guards-on-ice move Aim and I are planning hits, that'll be another 800 for 4160.
If Meleeman starts off a round with Tear asunder, that'll increase our damage output by 255 per turn, assuming we all attack without dodging and we all hit.
I can do a one-time blast for 200 (400 elemental).
And... that's all I've got. Any ideas?