>Yes, make an arrow which is designed to rebound off of people after hitting them, then attach the pocketwatch to the arrowhead.
Ballistics, dude. Simplest thing to do is probably exploit the other guy's shock and grab/squash the heart before he can get to it.
You guys got me. (They sound useless, though, don't they?) Respectively [spoiler]Echoes in part 4[/spoiler], obviously, [spoiler]The Lock used by a minor villain at the start of part 4[/spoiler], [spoiler]Jolyne[/spoiler] of course, and [spoiler]Tower of Grey at the beginning of part 3[/spoiler], F=ma and loving it.