Mantis to appear in Avengers Age of Ultron

Joss Whedon has mentioned that there are four key roles in Avengers Age of Ulton. We know that Scarlet Witch and Black Widow are two of them. We have talked about Shuri, and possibly a connection to Amadeus Cho through a character with the last name of Cho. Here is another possible female character.
Schmoes Know are reporting that they have info that Mantis is appearing in Avengers Age of Ultron. According to their source:

This would seem to make a lot of sense as she 1) has direct ties to Thanos, 2) has even stronger ties to Vision, Quicksilver, and Scarlet Witch, 3) has a personal vendetta in the comics against Klaw and, most importantly 4) has been a prominent member of both The Avengers and the Guardians of the Galaxy.

They go on to say:

If Marvel is looking for a way to connect these two teams together in Infinity War (as our source is projecting) than Mantis makes sense. Although our source is clear that they are not 100%, as we said, ties to people working on Age of Ultron are saying this is the name they are hearing over and over again.

Mantis first appeared in Avengers #112. Copies go from very reasonable to outrageous.