The GoodWarcraft II is a classic in its own right. Relying on the yet unrealized potential of the real-time strategy genre, Warcraft II set the rules of the game with an amazing game which superceeded it's predecessor in every way.
The first thing you notice in Warcraft II is the amazing graphics, starting with the great menu interface, which is extremely well-drawn and well-thought out. Then there's the credits, with probably the smoothest SVGA scroller seen to date on an Intel machine (I had a 486 DX2/66 at the time) and the amazingly smooth game engine: Great graphics, along with smooth screen scrolling and sprites, everything in Warcraft II screams speed and beauty. Then there's the music, in which Warcraft II certainly does not lack: some of the best music in any game, let alone RTS, to date and fits the gameplay perfectly. The MIDI soundtrack is simply mind-boggling and rarely gets the appreciation it genuinely deserves. Warcraft II certainly does not lack in gameplay either.
On top of it all, Warcraft II offers network play! Here's a concept! Even though same year's Command & Conquer did offer network support, Warcraft II came out earlier and beat C&C in that too as it featured very smooth network/modem gameplay. Even I, though not being a big RTS fan, found Warcraft II's network support to be greatly underappreciated.
The BadFor one, I could never be bothered to complete it; for some reason, the built-in scenarios get just plain boring after a while. Another complaint is the ridiculously stupid computer AI - the computer is not being smart, he just cheats with the ability to control units much faster than a human player. Unless you're very well-trained, this leads to very short lived human-computer mélees. Shame.
The Bottom LineA classic game which brought RTS to the spotlight again. Until Warcraft II saw the light of day, there hasn't been a single game other than the magnificent Dune 2 to play.