Best rivalries in manga and anime?

[Papasmurf]

Like Hector's thread, but srs

I'd say

Guts/Griffith (Golden Age only)

Tekkaman Blade/Tekkaman Evil (Space Knight Tekkaman Blade)

Vash/Knives (Trigun)

Light/L (Death Note)

Joe Yabuki/Tooru Rikiishi (Ashita no Joe)

Char/Rei (Mobile Suit Gundam)

Akira Fudo/Satan (Devilman)

 

[Yoshi]

Gon/Killua should be in that list too, although sometimes people don't consider them to be rivals.

 

[Papasmurf]

Some honorary mentions:

Hikaru/Sai and Akira Toyou, Sai and Koyo Toyou (Hikaru no Go)

Jonathan Joestar and Dio Brando (JJBA)

Maya and Ayumi (Glass Mask)

I'd have included Naruto/Sasuke if not for how overtly gay and one-sided it became during the 5 Kage Summit arc, and Yugi/Kaiba if it weren't for Atem/Yugi randomly considering him a friend as early as Duelist Kingdom instead of a hated adversary at that point. I also kind of like Ryoga Hibiki and Ranma Saotome's rivalry but the series is too slapstick and basic for it to count.

 

[Papasmurf]

Gon/Killua should be in that list too, although sometimes people don't consider them to be rivals.

Then they aren't good rivals lol. At least the Goku/Vegeta rivalry has a clear blooming point and both parties have obsessed with defeating the other even at great peril (although obviously very much more one-sidedly from Vegeta).