Form to update referenced datasets

Hi all,

I have two different datasets connected (Monsters and Items), with references between thens. Eg. Items dropped by X Monsters, and Monsters that drops X,Y,Z items.

Now, I am creating the form for the community to update the databases. In the monster adding form I thought that the best option to select which items do that monster drop from the items dataset (lets say >10,000 items).

So, I don´t know how would you do this? Any ideas?

Thanks in advance!