Mythril Beastcoin  

These are fairly easy to obtain while chocobo digging as well. Areas to get them include Gustaberg North; Gustaberg South; Konschtat Highlands; Pashhow Marshlands; and Rolanberry Fields.

I've done this several times. Head into Gustav Tunnel, cast Tonko: Ichi, find a Goblin Reaper or Goblin Robber, Steal one of these from them (I have a higher success rate from Reapers for some reason), Mug (if it was available), then Hide, wait 5 minutes and repeat. Of course, Poachers are to avoided, because they only carry Crossbow Bolts.

However, I would avoid Stealing and Fleeing to zone if you do not have Hide. PTs tend to level here, and zoning gobs to them will **** them off. Hell, if you do it more than once, they might call a GM on you.

THF's can Steal Mythril Beastcoins from Moblin Repairman in Oldton Movapolis.

I got one from a Goblin Furrier in Sauromugue Champaign it was a drop.

I just got one of these off of a Goblin Shaman in Rolanberry Fields (dropped, not stolen). I've killed dozens of them and this is the first one I've seen, so I'm guessing it's an extrememly rare drop.

Many ways to get these. Digging is one but its not very often you come across them. So far the best way to get them is to either plant tree cuttings and harvest them or steal from goblins that other guy posted