The Australian winger, who is set to leave at the end of the season, played his part in the dramatic 12-10 win against Warrington Wolves.
Hull have finally won at the famous stadium at the ninth attempt of trying.
Michaels, 28, said: “It feels a bit surreal at the moment, we’ve got the monkey of the back and the town needed that.
“It means so much to the local boys in the team and that’s what we were doing it for – guys like Danny Houghton and Gareth Ellis.
“I can’t wait to have a few celebrations with them.”
Hooker Houghton’s 78th minute tackle to deny Ben Currie proved crucial.
“I thought we were gone then,” conceded Michaels.
“Currie was going to score but that’s Danny’s game; he turns up and does that for us. I can’t talk him up more.”
Michaels almost scored himself as treble-chasing Hull mounted their comeback from 10-0 down and was brilliant under the high ball.
“I just missed out on a try when (Stefan) Ratchford came up with a big play but my game’s bringing the ball back and if we win I’m happy,” he said.
“We were always in it, we never give up and always find a way to win, and maybe (Marc) Sneyd’s goal kicking saved us.
“I’m leaving with a Challenge Cup win and that was all my goal and focus.
“Hopefully we’ll get a crack at another one.”