Each character has a personality. It's just hard to figure it out for some.
Ridley is obviously a ruthless and sadistic space monster who shows no regards to who he murders.
Bowser also doesn't show much remorse when he tries to conquer the Mushroom Kingdom, though unlike Ridley, he does have a rarely known soft spot, especially with Bowser Jr..
Ganondorf is obviously the number one villain when it comes to being ruthless, sadistic, and a manipulator, as he'll go so far as to murder his own followers, just to get what he desires. When it comes to being cruel, Ganondorf puts most other villains to shame.
Well I think Ridley thinks about it...but then just does it anyway. Like when Samus tried to befriend him on K-2L and Ridley was like "lol imma murder you instead" but then her mom took the fall and now they hate each other ^_^
Just gonna say this about Ridley, but it doesn't have to be
the Ridley from the Metroid games (like the primary Ridley that Samus fights in all the games besides Fusion and Other M and Super Metroid [depending on who you talk to, though it could be the same Ridley from Metroid and the Prime games]). Considering we now know Ridley has been cloned and seems to be its own species rather than just an anomaly, it could be a Ridley that's just another specimen from the species and, to work with size issues, it could be a younger Ridley that hasn't fully matured yet.
And to go to stage discussion, just thinking of some stages that would be cool to show up or be put back in from previous games:
-Termina (Melee)
-Saffron City (SSB64)
-Corneria (SSB64...I always liked it being bigger, never really liked the Melee one)
-Peach's Castle (SSB64, whatever it's called)
-Hyrule Castle (SSB64)
And some new additions...
-Chozo Temple (Metroid Prime)
-Norion (Metroid Prime 3: Corruption)
-Alinos Gateway (Metroid Prime Hunters)
-GFMC Task Force Herakles Crash Zone (Metroid Prime 2: Echoes)
(there's actually a lot of awesome spots from the Prime series that could work as a stage)
-Jolly Roger Bay (Super Mario 64)
-Dire Dire Docks (Super Mario 64)
-Final Boss Battle Area (Yoshi's Island)
-King Kut Out Boss Battle Area (Donkey Kong 64)
-Facility (Goldeneye 007)
-WarioWare x2 (A follow-up stage to the first WarioWare stage)
-Pokemon Stadium 3 (You know there's going to be one)
So many more awesome locales in Nintendo games, almost too many to actually think of.
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