Nearly thirty years later, there's not much left to say about Sonic the Hedgehog 2 itself.  You know the story already: Doomed planet. Desperate scientists. Last hope. Kindly couple.  Egg-shaped madman.  Courageous hedgehog (and fox).  Casino Night Zone.  Chaos Emeralds.  For anyone who somehow hasn't played Sonic 2, this re-release is a must-own simply to play the game.  For the rest of us, Sega has added some new features and some quality of life enhancements returning from past versions to make the base game better.  The best addition is that the drop dash maneuver from Sonic Mania which allows Sonic to build up a spin dash while in midair.  Having this skill available changes up how parts of the game are best approached and helps to keep Sonic moving at times when, in the old days, you'd have to stop him to rev up some speed.  HD rumble brings vibration to actions such as spin dashing and breaking monitors.  Ring Keep Mode from past recent re-releases is also included which allows Sonic to hang on to half of his rings when taking a hit instead of losing all of them, plus he starts each act with ten rings already in hand.  Finish the game once (with or without all seven Chaos Emeralds collected) to unlock Super Sonic Mode which starts Sonic off with all of the emeralds and fifty rings at the start of each act, allowing him to become Super Sonic right from the start.  The game's stage select is available from the menu, too, and I had a lot of fun turning on all of these new additions, jumping ahead to the stage of my choice, and wreaking havoc with all of my new toys.  If you don't want any of these enhancements, they can all be turned off.  To complete the package, the original game's competitive two-player mode is included as is Knuckles's starring role in Sonic 2 as a main menu option right from the start, no unlocking or lock-on technology required.

Outside of the main game, the usual modern re-release trappings are here.  Save states are available and you can lock your favorites so they cannot be overwritten.  The game will track how many rings you collect in a row without losing any and then, at the end of the game, will post that number to an online leaderboard where you can compete against both friends and players around the world.  There's also a new challenge mode that tasks you with collecting one hundred rings and reaching the goal in Emerald Hill Zone Act 1 as quickly as possible, and then those scores are posted to leaderboards as well.  These are fun little additions, although I didn't see the need to spend much time with them.  I can see how speedrunners will have a blast with them though.

Games like this re-release of Sonic the Hedgehog 2 are not the kind of games that you complete and then forget about in favor of next week's big new release.  This is the kind of game that you keep on your Switch to dip back into from time to time, exploring some new part of it and experimenting with the drop dash to see how it changes the experience or mucking around with Knuckles armed with all of the Chaos Emeralds.  It's a well-earned part of the canon of noteworthy, replayable games, and in this format it's definitely earned its place all over again.