Tyson - an Oakleigh Chargers product - said he got the call regarding a potential trade to his home city while overseas attending former team-mate Setanta O'hAilpin's wedding.
And upon returning to Melbourne to finalise a switch, Tyson, 20, said he was impressed by how the Demons presented themselves under new coach Paul Roos.
"I was impressed by the presentation from the Dees," Tyson said.
"It was very exciting. He (Roos) was very honest, and that was something I really appreciated.
"He said, 'We need to add some midfield depth. I've followed you for a couple of years, and we're excited by the proposition of putting you through the midfield and play that sort of inside position'."
Tyson said the coaching panel, along with a greater spread of on-field mentors, made it easy for him to agree to a trade to Melbourne.
"Both clubs are in a pretty similar position, there's probably more senior players here - which was something the Giants missed last year," he said.
"Development here is something I thought'd be great, being able to learn off Paul Roos and George Stone and Ben Mathews.
"That was something I was really enticed by."
Tyson said he had not thought about leaving GWS until he received messages in Hawaii that he was one of the Dees' targets to bolster their engine room.
"I was contracted, so I hadn't really had too much of a thought about it," he said.
"But when my management said there could be a pretty serious chance to get back, that's when I thought it would be great to return to Melbourne and be around family and friends again.
"I enjoyed it up there - they're an exciting club at the Giants, and I've got some close mates up there.
"So I guess it was a tough decision. But I'm very excited with this."
Tyson has had shin and posterior cruciate ligament injuries so far in his fledgling career, but felt he was ready to complete his first full pre-season.
"We just had a couple of little meetings there with (elite performance manager) Dave Misson and the physios, but I think I'll be rolling into pretty much full training," Tyson said.
"There might be a little bit of modified stuff, but hopefully early days I'll be in full training."