Now Samus can grab items by shooting them with the Grapple Beam. Why not?

In the original game, item pickups are inert for all projectiles.

grapple-pickups patches the block collision code to make grapple count as picking them up. Uses some free space in bank $94.

Known Issue:

Picking up a suit with the Grapple Beam will leave the electric sounds on throughout the suit effect, until Samus leaves elevator pose.

This can happen in the vanilla game: fire the grapple beam just before picking up Gravity Suit. If done late enough, it doesn’t complete before triggering the pickup, and the Gravity Suit is electric.

I’ve tracked a root cause of the problem, but I haven’t decided what to do about it. And it’s tripled the length of time I’ve spent on this. So, here’s v1, no grapple fix.

(Root cause: the suit flash code sets $C856—stop grappling—as the grapple beam per-frame code pointer. But with Samus in elevator pose, actually calling that code is skipped. $C856 never gets to clear grapple state and change the pointer to $C4F0, beam off. Which happens to also be the only value that prevents re-starting the sound.)

Credits:

This patch could not exist without docs by Kejardon, pjboy, Scyzer, and the rest of MetConst.

MIT License.