The 19-year-old has cut an impressive, composed figure since making a shock debut in last weekend's Edinburgh derby win over Hearts.
With James McPake and Tim Clancy facing a race to recover from injury, Forster will be in contention to start the Hampden showpiece against the Hoops next Sunday.
Aside from the obvious desire to become a club legend by helping to end a 111-year hoodoo, the Gorgie-born centre-back would draw some added satisfaction from defeating the Glasgow giants.
"At Celtic, I had a discussion with the head of youth and he said at that time it was unlikely that I'd get a pro contract. That was three years ago," said the promising defender.
"Whenever you're released by a club and play them again, there's always an edge. That will always be there. Hopefully I will give the manager here a headache for the final by continuing to perform well on the pitch and in training. There's an extra incentive for me every time I play against Celtic now."
Forster has bounced back impressively from his Parkhead disappointment in recent years, and describes joining Hibs as the "best thing I've ever done".
He continued: "It is hard to sum up what the last couple of weeks have been like. It's happened so fast, like a whirlwind. If you'd asked me a couple of months ago if I'd be in this position, I'd have said 'no way'. To make my debut at Tynecastle in the derby was unbelievable.
"It justifies my decision to come here after leaving Celtic, 100 per cent. It wasn't going to work out for me there and joining Hibs is the best thing I've ever done.
"Hibs are renowned for bringing youth players through and that's been proved. It would be a dream come true for me to play against Celtic's first team and win. I'd be lying if I said I haven't thought about running out against them at Hampden in a Scottish Cup final."