If you can guess who made them all you get a cookie.
What they replace: Be aware that the Dangerous Duck also comes as Hammer Bro Variant.
Refer to this site for the enemy names:
http://www.mariowiki.com/Wario_Land:_Su ... _3#Enemies
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Left = Enemy Name
Right = Enemy Replacement
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Dangerous Duck = SMB2 Blue Snifit
Debidebi = SMW Swooper
Gaugau = SMB2 Blue Snifit
Guragura = SMB1 Hammer Bro
Fireballs = Podoboo
Wanderin' Goom = Blue Shyguy
Spiked Balls = Blue SMB1 Goomba
Penkoon = Hammer Bro
Harisu = SMB3 Spiny
Yarikuri Obake = SMB3 Boo
Yadora = SMB3 Crab
Be = SMB3 Fly
Thunder = SMB3 Airship thing
Bird Statue (not named) = SMB3 Bowser Statue
Boulder = SMB1 Goomba
Floater = SMB3 Brown Platform
Chicken Duck = SMW Yellow Koopa
White Puff = Light Blue Bot (from Zelda)
Bucket Head = SMB2 Blue Snifit
Konotako = SMB2 Bomb
Yaburiki = SMW Rex
Wagon = SMW Mega Mole
Pirate Goom = SMW Goomba
Pouncer = SMW Thwomp
Chikuri = SMB2 Sparky
Ukiwani = SMB3 Green Cheep Cheep
Pecan = SMB3 Red Cheep Cheep
Pinwheel = SMB3 Blooper
Goboten = SMW Blurp
Togemaru = SML(?) Goomba
Watch = SMW Swooper
Paidan = SMB2 Hoopster
Pikkarikun = SMW Lakitu
Dropper = SMB2 Ninji