Held Items on Wild Pokémon

[Lysander]

Several Pokémon have a small chance (usually 5%) of having a held item, and some have a fairly high chance of holding an item whenever you encounter them. What are some of the best items you've managed to obtain from wild Pokémon?

I've previously managed to catch a Wurmple early in Alpha Sapphire that was holding a BrightPowder (and I only realised it was holding BrightPowder because I missed with Tackle). I also used to use Thief on Luvdiscs frequently to get Heart Scales from them. Thankfully that isn't necessary to do anyomore in SwSh since you can relearn old moves for free.

 

[Palamon]

Lucky Egg Chansey in HG/SS was my best. But, in my case, I actively hunted for a Lucky Egg Chansey to get one. It took a lot of tries. Once upon a time, the Lucky Egg was an extremely hard to find item and was only available through wild Chansey.

I've also found a Light Ball Pikachu a few times, as well as some Pokemon with rare berries on them in Gen IV.

 

[Sheep]

the most fulfilling thing was spending ages trying to find chansey in gsc (1% rate) and then finding a lucky egg on them (5% rate)! kid me was so happy when looking each time i got one

 

[Megan]

I didn't know that random Pokemon encounter could yield held items for the longest time. Sure, I was aware that Ho-Oh in gen 2 had its own item that you could obtain by either catching or by use of Thief. However, it took me until gen 3 to actually notice that there's a lot of wild Pokemon with items on them.

I have done my fair share of Heart Scale robbing, however probably my most glorious event was in Moon. It was very much the last time I attempted to complete the Pokedex (well, it's also the most recent game I played) and the I did so by abusing the usefulness of held items.

I bred a competitive Scyther, got myself a good Thief user and then just kept farming Metal Coats from Magnemites for about an hour. Then I threw the breeding rejects into the GTS, each of them holding a Metal Coat, demanding some of the harder to get trade evolutions. Lo and behold: it worked wonders!