Foster's Reactions Carol: Heard it through the grapevine. She's angry, but when she finds out the why she will understand more. She'll be mad he left so many people, but she relates. Not like she didn't do the same thing once- she knows how it is on the other end, risking yourself to save others then leaving people you loved behind. She will feel angry for not being told- t would have been safer for her to got through that damn thing. Odds were she'd have survived or come back (in her own mind, at least). In the meantime, she'll eventually start strategizing. They're going to need leadership eventually, just like she told Steve.
Bucky: Will probably hear it from Steve. He was never very close to Tony, but there's some guilt left over that they never buried the hatchet. He'll be there for Steve, Natasha, Clint, or anyone else who needs him as someone to listen or just sit in silence with.
Mantis: She's going to feel this one. She realizes things are amiss as she feels the mood shift. Despair and sadness. She knew Tony and had not gotten close, but she does mourn the loss. He was a good man.
Melina: She did not really get to know Tony Stark, but she feels some pity for the others. She also realizes the world has lost a great mind and this place will be without a leader. She will step up and help int the science department as needed.
Miles: He liked Tony! The guy was great to them. He's going to find Tim as soon as he learns what happened, though.
Sally: She's sad about the whole thing, but she's more concerned about how the others are taking it.
Helena/Madison: Helena cares to a degree in that there isn't going to be leadership and shit, she's glad she's away from that. Madison doesn't care. It's not the Coven and not anyone she really knows well.