I'm not going to establish what Virtual On is, because most people should know what it is. Otherwise:
http://en.wikipedia.org/wiki/Virtual_On
Sega Ages Virtual On in particular is a direct port of the original Virtual On from arcade to PS2. If you've played Virtual On for the PC, it's the exact same game, except it looks and sounds better, and runs at a full 60 fps like the actual arcade game. Also, they added some extra content:
- - The game comes with a VR collection and an art gallery, like most contemporary arcade-to-console ports.
- You can record and save replays like in Oratan.
- All the colour schemes in the PC game are available.
- You can play as Jagurandi or Z-Gradt, the bosses of Virtual On, like in the Saturn version of the game. Z-Gradt cannot be played in split-screen or in the regular arcade mode, and has a seperate Z-Gradt mode.
- Ranking mode is probably a time attack mode of the game, with continues disabled.
- Assault mode is a mode similar to Oratan's Infight mode. In this mode, you can't fire projectiles unless you're in the air or are using your CW, forcing you to use melee attacks. To make up for this, dash attacks are melee attacks.
- Chibi-chara mode is what it sounds like.
- There's an option to turn on extra special moves, similar to the specials in Oratan. If enabled, Apharmd can use Kick the Dynamic, Raiden can armor break, Fei-Yen can enter hyper mode manually, etc.. Just like in Oratan. Temjin, Dorkas and Viper II already have specials, so this doesn't affect them.
- I don't know about the original arcade cabinet or the Saturn version of the game, but Sega Ages comes with Fierce difficulty, which actually is hard. They use the Very Hard AI (which isn't hard by itself) and give them infinite ammo. Watch out for Beldgor CW spams.
If you want to play against me or someone from virtualon.net though, I recommend clearing Fierce without continues first. Most of us are very, very good at the game, it's almost funny when we try to invite a new player into the game, only to scare them off.
I honestly wish they'd port Oratan though, since although the original is more memorable and still a great game, Oratan still has some of the best gameplay in the series overall.