I don't have the context of your previous thread, but how would burrow let you fake breaking objects?
standard burrow allows you to move through dirt and earth. some version even let you leave a tunnel. specific versions of burrow allow you to move through stone as well, again, some let you leave a tunnel.
if one specifically has a form of burrow that is not earthglide/phaseshifting, ie: actual digging, AND it allows passage through rock and stone, AND leaves a tunnel, then you can fake breaking objects. whether you dig or focus your chi and hit a structural weak point is mere fluff at that point. as far as the rules are concerned, you can create a passage through rock and stone, however you
describe that you did it.
now keep in mind, that the objects i'm intending to have meant and was talking about breaking are walls, doors, ceilings, floors, pillars, and so forth. i'm not meaning sunder attempts against held objects.
Manyfang morphed into a ward cestus? Add +3 to your multiplier.
Ooo, forgot doorbreaker. X2 to wood.
Ooo! Rust Cubes! (100 gp) Stonebreaker Acid! (20 gp) A Sprayer (14 gp) to spread out the stonebreaker acid over a 10' x 5' area!
now we're cooking with grease! =D that's some good ideas. maybe i can make a magic item that coats his skin in stonebreaker acid, and even duplicates the rust cube effect.
i was looking at a custom item using that amazing machine spell from the SpC for the x3 damage versus objects. and maybe a custom treant-based item for the x2 versus objects....