Honestly, I'm going to say it'd be a toss up between either the Golden Diva or the Shake King. The former is an interesting foe with a ton of different attacks, whereas the latter is a surprising dangerous opponent with multiple phases and some powers which are incredibly surprising given his character design.
That said, here are my views on all the final bosses from the Wario Land series:
Wario Land 1: Eh, it's a fight I guess. Never liked how you fought the genie instead of Captain Syrup though (especially given her boss appearances in the sequel), and the whole atmosphere of the battle just kind of felt lacking overall. Needed to be a bit more 'epic' if you ask me.
VB Wario Land: Never played it. Looks interesting in design and concept though.
Wario Land II: Wait, which of these battles is the final one again? You fight Syrup three times, a giant fish once, a bubble creature once, a ghost once and end up rebattling the Giant Spearman in the ultimate finale. Still, I liked most of them more than Wario Land 1's final boss, even if none of them really felt very 'final'.
Wario Land 3: Loved this battle, since Rudy was a great opponent and his being able to kill you gimmick actually made things a tad tense too.
Wario Land 4: See start of post. A great final battle for a great game.
Wario World: Do you really need me to tell you this thing sucks as a villain or final boss? It's bad enough we got royally screwed compared to Japan here, since they got a whole second phase to the boss fight, but even with that phase it's not particularly interesting and doesn't exactly scream 'amazing villain'.
Wario Master of Disguise: As an idea, Terrormisu had potential. As an actual opponent? Not really done that well, especially given how 99% of the battle was basically mini games set in random challenge rooms where you only had one attack to dodge each time, or how her design looks utterly atrocious in general. Still, the music was nice.
Wario Land Shake It: See intro to post. Actually really liked this fight.
But yeah, which do you think is best and why?
That said, here are my views on all the final bosses from the Wario Land series:
Wario Land 1: Eh, it's a fight I guess. Never liked how you fought the genie instead of Captain Syrup though (especially given her boss appearances in the sequel), and the whole atmosphere of the battle just kind of felt lacking overall. Needed to be a bit more 'epic' if you ask me.
VB Wario Land: Never played it. Looks interesting in design and concept though.
Wario Land II: Wait, which of these battles is the final one again? You fight Syrup three times, a giant fish once, a bubble creature once, a ghost once and end up rebattling the Giant Spearman in the ultimate finale. Still, I liked most of them more than Wario Land 1's final boss, even if none of them really felt very 'final'.
Wario Land 3: Loved this battle, since Rudy was a great opponent and his being able to kill you gimmick actually made things a tad tense too.
Wario Land 4: See start of post. A great final battle for a great game.
Wario World: Do you really need me to tell you this thing sucks as a villain or final boss? It's bad enough we got royally screwed compared to Japan here, since they got a whole second phase to the boss fight, but even with that phase it's not particularly interesting and doesn't exactly scream 'amazing villain'.
Wario Master of Disguise: As an idea, Terrormisu had potential. As an actual opponent? Not really done that well, especially given how 99% of the battle was basically mini games set in random challenge rooms where you only had one attack to dodge each time, or how her design looks utterly atrocious in general. Still, the music was nice.
Wario Land Shake It: See intro to post. Actually really liked this fight.
But yeah, which do you think is best and why?