This is the Reaper Bones 5 Dungeon Dwellers Expansion from Reaper Miniatures 2019 Kickstarter project; it includes 40+ plastic miniatures. The last image shows the  minis scheduled to be included in this set at the time of the Kickstarter; I don't know if that is everything that was ultimately included, or if any of those shown did not make it into the final product, as sometimes happens with these projects.

These minis are new, and have not been removed from their packaging; the box is still sealed.