Well, after re-trying it, I was able to unpack the file. However, I ran into a different problem. Apparently, the master colossus has an entirely different .frm from the other colossi; the .frm is marionette_b4step_framework.frm, whereas the normal colossus frame is just marionette_b-framework.frm. I tried doing a basic .pmg swap, and also tried to swap the .frms of the master colossus and the regular colossus (the separate .frm for the master colossus seems to be related to its special gauntlets, judging from the .pmg viewer). I have a modded client through frontend, and I put the swapped meshes/.frms in the mabinogi->data->gfx->char->monster->mesh (I then created a folder for the .frms and meshes called marionette, and stuck the files in there). I then repacked the client, and ran the game...but I didn't notice any change. When I equipped the vine marionette, the vine marionette came up (swapping the .pmgs should've brought up the master colossus, but nothing happened). Any clues as to what I'm doing wrong, there?