On top of the list is Mega Extra Hot!

Mega Extra Hot Sardines is on top since i cant recall the other extra spicy, extra hot sardines ive tried. Sardines in red label are called hot but actually they are not as hot as you want them to be. Anyway I will be hunting for other extra hot and will try them but so far Mega Extra Hot Sardines made it.

UPDATE Octorber 27 2023
Golden Town Super Hot

This is good alternative if Mega Extra Hot Sardines is not available, also this is cheaper. For the hot rating, i say this is good, the the hotness is well blended like mega extra hot sardines. For the taste i would say dont put your expectations too high, like cheap sardines dont expect that much. But compared to Vinta Xtreme Hot & Spicy althought the sardines taste is acceptable still this is better since hotness was done correctly. Taste 5/10, Spicy 8.5/10

UPDATE July 11 2023
I tried the Vinta Xtreme Hot & Spicy - it has a different taste to it, also the spicy is more of like an after thought, like they just added a spicy powder to the sardines. In terms of taste, this is a 6/10, spicy/hot  8/10 but ill drop it to 5/10 taste sort of fake, it wasnt well blended together in terns of taste, its like you have this spicy bite from nowhere instead of a good well rounded well balanced spicy bite.