Look for anyone that have unfortunate lives and attempt to improve them using the crystal
...
especially if no one will notice them missing if something goes wrong.
Unfortunately, you still don't know how to use the crystal. "Good" intentions and staring at it intensely can only bring you so far. But you can surreptitiously survey the village for those down on their luck!
This fares better. You don't do anything too specific; instead, you opt to simply prowl about in the sidelines and hope you don't stand out too much.
You only find one person with your generalized plan: a beggar. One that doesn't seem to actually get anything from their begging and is forced to survive off of scraps that they find. He appears to be in his... thirties? Not a specimen of peak physical health either way, as his poor living conditions have clearly taken much from his body. He hangs around more highly trafficked areas and it's undeniable that many villagers see him routinely. Despite this, not a single person paid any attention to the poor man. At night, he retreats to a well-worn makeshift abode between buildings.
This observation was all done from a respectable distance. Physically abducting him would likely pose little to no risk, but that's not the only option if you wish to.. improve him. Somehow.
(For the time food and supplies are not an issue as you can just barely sustain yourself on the land and surrounding area. It's not fun, though.)ResidenceAbandoned Hovel
Possessions - Strange Crystal - A small dark-green crystal said to be capable of enhancing and improving individuals. Uncomfortable to hold, and faint beating can be heard from within.
Knowledge As far as you know, nobody has noticed or otherwise paid much attention to you yet. Though continuing skulking in the shadows wordlessly would most likely prove suspicious eventually. Otherwise, you have a potential candidate for the crystal. Still need to figure out how to use it, though.