Love the expanded artifacts in S2, however I would like to see a bit more with regards to collectable super rare drops.
Many other RPG’s do it to epic effect (Diablo 2 being an example). So why not design and add in super rare named artifacts?
One idea would be to design one for each ‘race’ of monster (fortress, berserker etc.) That has 2 traits on it that are primarily designed to compliment the overall traits of the race (but can be useful to other creatures of course).