I'm looking for a Steve/Tony where Loki has shrunk Iron Man, armor and all. I believe it was because Tony was running his mouth at Loki. I know there is a smutty scene towards the middle involving the shrunken Tony and Steve. At the end of the fic Iron Man goes out with the team to fight Loki again despite his predicament and really only manages to harrass Loki. The spell either wears off or Loki reverses it causing Tony to grow giant. I don't know if its a finished fic or not but I'm certain I read it on AO3.
Thank for all the help=)