Stonebound Arms is a rare major card out of the New mechanic pool. Attunement: your Main attack deals Stone damage. One Attunement per input.

Stone hits build Crumble toward Sunder — armor break plus Stagger — and steady Main pressure outpaces the meter's decay. Excellent into bosses and armored elites; Seismic later makes each Sunder explode.

You can take it once · it only turns up when your Main ability can actually use it · it can be offered for 11 of the 34 abilities.

It pushes your build toward Stone.

Only one card can reshape that ability this way — this one, or Flamebrand Arms, Rimebound Arms, Stormbound Arms, Venombound Arms, Bloodsworn Arms, Lightsworn Arms and Voidtouched Arms. Take one and the rest are gone for the run.