q about nemesis mod rolled on map``

Wealth isn't a nemesis mod, it's one that any rare can have, but is exceptionally rare. Inner Treasure is more common from what I've observed, however it's still the rarest nemesis mod. Whether the risk is worth it depends on how well you can handle the other nemesis mods. Storm Herald and Corrupting blood are the ones that players typically have more problems with, but both can be beaten if you know how to play around them.

Inner Treasure and Wealth can appear on rare monsters in Standard, however the nemesis mod ensures that every rare on the map has a nemesis mod on them.