Is there a way to change the properties of an Extended Sprite without patching in ASM? I'd like to change the Graphics Page bit to the other page but I couldn't find anything in the RAM Map to do that.
What you could do is run some code each frame to search through the extended sprites area of the OAM ($0290-$02DF according to the wiki's OAM map) for tiles with the same number and properties of the ones used by the hammer, and then change the properties of the ones you find. If you do this, remember that each OAM slot consists of four bytes, and that the ones you want to check are the two last ones.
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