what
Stage 4 is like the best stage in all of the games. Especially UFO, since the rest of the stages are just bad.
I think my favorite stages were 2 in EoSD and UFO, 3 in MoF, 6 in IN, and 5 in SA PCB.
But that's just me.
The Extra Stages save for 12 (I actually beat that one) all get my eternal loathing though. Moriya's Iron Ring, Rorshach, Flying Phoenix, EX-Keine, EX-Chen, EX-Kogasa, Nightmare of Heiankyou, Green UFOs of Loyalty, I could go on forever.
I recently bought a Team 9 cape in RuneScape :3