Idk why this went through my head yesterday afternoon, but it did and i'm anticipating the flood of Xj-9/jenny answers.
E-102 "Gamma" (Honorable Mention to his brothers)
E-123 Omega
Meta Cooler (Dragon Ball Z)
Megazord (Mighty Morphin' Power Rangers)
Metal Sonic (Honorable mention to Shard from the Archie comics)
Tom (Toonami, MkII being my favorite version)
Gypsy, Tom Servo, and Crow (Mystery Science Theater 3000), with Kevin and Bill being my favorite versions of Tom and Crow respectively.
Machine Man (Aaron Stack, Marvel comics)
Protoman and Bass (Megaman main series)
Metabee (Metabots)
*edit* Robbie the Robot (absolute Classic design)
*edit again* i forgot Metaton (or however you spell it)

Rockman

Zaku II, Nick Valentine, ED-E, and Robocop among others.

Also, for my horny answer, Haydee. :P

BX-Commando Droids (Star Wars)
X-49 (Samurai Jack)
Scaramouche (Also Samurai Jack)
Panzerhund (Wolfenstein.)
T-800 Terminators (From Terminator... duh.)
Sentry Bots (Fallout)
Dewdrop (Atomic Heart)

Sonofabitch, i forgot him too and the Iron Giant (and plenty others as always)

I think these technically count, so also

Patriots (Bioshock : Infinite)

Also Metal Sonic, i will not apologize
And E123 omega

also Blade Wolf

....well i cant NOT disagree with that

Penny from RWBY man that bitch is so fucking hot I could fuck her slimy robo asshole all day long and make her short circuit her pussy juice all over my jiggling balls until she's squeezing them hard and I scream and cry and die from pain

Are Nikke's considered robots?

If so all Nikkes are my favourites, specially Rapi, Volume, Blanc and Noir

p03 from inscryption, he so silly

do animatronics count…?

I find it horrifying Bender is not on this list

I can't be the only one who was down bad for Courtney Gears from Ratchet and Clank, right?

Probably any robot you name I'll adore, however GLaDOS will forever take the cake

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