Some sequels are better than their originals, and Mega Man Zero 2 is one of those games.
Gameplay: If you enjoyed the first MMZ, you will not be disappointed. You still jump, use your weapons, dash, and wall kick, just like the Mega Man X games. Like its prequel, you can equip weapons to the B and R buttons (which is a great idea for a Mega Man game), and the game is very hard, which makes the game not for everyone. You can also collect cyber elves to boost your vitality, your abilities, and even "hack" into stuff, like switching your rank to A, and even turning enemies into Mettaurs (for real). You can also level up your weapons by killing a certain number of enemies with that weapon, and it gets upgraded bu one level. Mega Man Zero 2 also introduces the Form System and EX Skills. In the Form System, you have to perform various tasks in a stage, such as collecting certain amounts of Life Energy to get the Energy Form, which makes Life Energy appear more frequently by defeating enemies, and killing a number of enemies with a Buster Gun to get the X Form, which makes your Buster Gun more powerful. In the EX Skills, by killing bosses quickly, you get their powers, and you can use them at any time in the game. With the same great gameplay, and cool new features (and Zero), the gameplay hits the spot wonderfully.
Graphics: The best 2D graphics I've ever seen since the PlayStation Mega Man games. All the sprites animate top-notch, and the backgrounds are excellent.
Sound: Again, MMZ2's sound is the best. The sound effects, such as Zero's gun, are thumbs-up, and the music matches all the stages.
Value: The game may be moderately short, but with the game's challenge, you can play this game for hours and hours trying to beat the game (of course) and getting all the EX Skills and Forms.
Tilt: Overall, Mega Man Zero 2 is one of the best sequels ever to come out. A rental if you're new to Mega Man, and a must-buy if you're a Mega Man fan or wanting a serious challenge. Another instant classic made by Capcom.