I can give you a rough estimate on numbers, but that's about it. Still, I'll give it a go.

Nack was introduced the same time as the Chaotix, as he was a part of Chaotix, until he sold them out to the brotherhood of Metallix, this was in the Knuckles Knockout special I believe, which was released around the same time as the comic was around #70-80

I have a gap in my collection, so I don't know if he returns anytime between then and the next time I saw him, which was in the early #100s (maybe somewhere around #115-120?), where he robbed a bank and challenged Sonic to catch him.

The next time he was seen was around #135, where he teamed up with Grimer in order to get to Shanazar, where Robotnik wound up after losing the power of the emeralds, Grimer needed his help because Nack could use his shrinking cartridges to get to Shanazar, which was the size of an atom.

He appeared in and out of the Shanazar Saga, but the last time I think he was seen was at the end of the Shanazar Saga, when it was merged with Mobius (around #155), and he was dragged away with grimer By Robotnik.

Thanks!

He appeared a few times with Sidewider and his gang, using his trademark shrinking capsules on the team.

He was shrunk to the size of an atom and it was thought he'd be gone for good, he eventually returned to normal, robbing banks on Mobius (it's unclear how he got there) under Sonic's very nose by sneaking in via a very very small crack and shrinking the gold.

He was scared off, stupidly enough, by sirens, he then reappered in the Shanazar story OTB mentioned.

I'm BA-AAAACK!

Yes, if I recall correctly, it was Porker Lewis who took the liberty of calling the cops while Nack was trying to squash Sonic.

Figuring there'd be too many of them, the weasel fled.

I like Nack from Fleetway. He's very technologically minded, which doesn't really show up in his other incarnations. In Archie he's just another gun-toting bounty hunter.

Nack was great. Because he was an arsehole. He appeared in Sonic Chaos as well, didn't he?

Sonic Triple Trouble.

Yeah i liked StCs nack, especially his "in it for the money" attitude he had, im surprised he actually stayed in the chaotix crew for as long as he did. (and what a great way to tie him in from Triple Trouble!)