GTS or the Simple Requests thread on Wifi are much easier than finding a wild Feebas.
GTS is the easiest. I don't know what you mean about the XD thing, but IMO Mt. Coronet is the easiest out of the other two, I mean, you can't compare that small piece of water to ALL of Route 119, even if there are 6 spots on Route 119 and 4 in Mt. Coronet.
What I'd do is:
I actually recommend catching one at Mt. Coronet because if you just fish at the edges, you usually end up finding one even though they only show up in 4 tiles.
Just got there with two Abras...
In my opinion, Close Combat's better than Drain Punch, since Iron Fist's power up iirc was only 20%, making Drain Punch only a measly 72 BP without factoring STAB, while Close Combat still sits at that high 120 BP. Your Mileage May Vary, since you're using Bulk Up, and I'm assuming you want to retain your Defense boosts.
1. Modest's generally better, since Milotic's not going to outspeed much anytime soon with its 81 BP.
Drain Punch is better for the Bulk Up set. The point is to also raise your defenses and stay in, healing + no defense drops is more beneficial, as the only thing really threatening it (in UU) as far as walling potential goes is Slowbro with Psychic. That said, Ice Punch gives you coverage over water types, Bullet Punch can deal with Swellow and other fast sweepers, and Drain Punch is the main STAB with healing.
Their nature/IVs are set at once when you talk to Oak (in which after you do so they swarm in Sinnoh). You'd better SR for one of them, rather than three. Or if you want, reset (save before talking to Oak) and catch all three and see which one has suitable nature/IVs, if you're not looking for something specific.
I can give you a Feebas I got from GTS :P, do you want it?
Trapping Blissey with Magma Storm and Exploding will likely be of more use than trying to metal sound and earth power it to death before it cripples/ ko's you with seismic toss(especially with little or no hp ev's). Even then, protect could potentially mess up your plan. I wouldn't run leftovers simply to feign a choice item at first glance, though almost all Heatran carry explosion anyway so its not much of a surprise. perhaps a pinch berry or something obscure like grip claw to make magma storm last the max amount of turns if you really want to use the move(I know its kind of gimmicky, but lefties is a big flag you aren't scarf'd).
You're missing the Pokemon XD Move Tutor that teaches Selfdestruct; that's where Snorlax learns it.
The official guide breaks down his quotes, but doesn't give number ranges, due to the workings of IVs not being the kind of info guides like that give.
"Can't be better" is obviously a 31 IV, but there's nothing on what range of IVs correspond to each message.
