The drop from Altereon (or w/e spelled) how exactly do you break his horns? his head is usually well above ground level. His most common hit spots are his hind legs and underbelly during attacks. Does it involve the walls? they seem to break way to fast.
The most common method is sleep bombing. This means you have someone (typically a gunner) put Alatreon to sleep at the start of the fight, and then the whole party drops Barrel Bomb L+ at his horns. Ideally most/all would have Felyne Pyro skill. After that, your gunner can continue to aim for the horns and should be able to break them throughout the course of the fight. If all else fails, you can also get him stuck in the walls, KO him, knock him over, or paralyze him, and get some free hits in on the horns.
You have to break both horns, not just one. And even then the drop rate is pretty abysmal.
First, I would get yourself a good crew together. Then get 2x Para LS and 2x Hammer. The LS guys go for the tail and back legs, the Hammer users go for Superpounds against the head. When he falls other use more super pounds against the head (or, if you were good at TP'ing Kushala you can time a TP as well - it's hard though). Every time Alba gets para'd, go in for the TP's. Don't use the walls until after the 1st para.
Good luck. You will need it.
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