It has a 5-color color identity, and you can get lots of mileage from this card with commanders like Jodah, the Unifier or Sisay, Weatherlight Captain that either cost or have an activated ability that costs
We should not forget a recent new addition to the scores of Infect strategies with the release of Dominaria, the infamous Yargle, Glutton of UrborgYargle, Glutton of Urborg
By forcing people to block with the Nemesis Mask, you can activate it a few times to drop some blockers and either kill them or keep a Masked creature from dying to combat damage
The downside is that shroud also means you can't target her with your own auras or equipment
In this deck having this happen is actually the lesser of the two modes, depending on your board state
You can even set up a little Rube Goldberg machine where this finds something like Vampiric Tutor to find the card you really want