Tier Change Suggestion:
UU->UUBL
Reasons:
1. Jolteon is tied for being the fastest non-mega Pokemon in the meta, while also having STAB-boosted Volt Switch for pivoting.
2. Jolteon's main rival for fast special pivot is Greninja, but Jolteon has a few things that make it unique. For one, Jolteon can counter opposing Greninja without needing to rely on a speed tie. It is also immune to paralysis and heals from Electric attacks, giving it sustain as well as a way to switch in safely. Jolteon's stats are mostly the same as Greninja except for one: while Greninja has a large attack stat that allows it to run mixed sets, Jolteon takes those points and puts them into special defense, which, combined with its lack of weaknesses, lets it survive some crucial damage, especially in the late game.
3. The main drawback of Jolteon is it's lack of coverage, meaning it almost always has to switch out against ground types in theory. I say "in theory" though because 3/4 of the OU ground types are weak to fairy, and Jolteon has access to Alluring Voice. With good prediction, a Choice Specs Jolteon can actually threaten a 2HKO into Garchomp, a 60% chance of an OHKO into Krookodile (100% with only 1 layer of spikes), and a guaranteed OHKO into Zygarde-10%. This leaves Excadrill as the only real counter to a late-game Jolteon sweep, but plenty of other Pokemon counter Excadrill very well.
4. From the UU side of things, Jolteon forms very strong cores with Pokemon like Mega-Drampa, Mega-Feraligatr, Shell-Smash Blastoise, and Clawitzer due to the fact that every ground type in UU is weak to water. Similarly, every grass type that resists Jolteon's STAB is weak to fire, meaning a well built team is very easily able to counter almost all of Jolteon's hard match ups. Jolteon instead is mostly checked by other electric types like opposing Jolteon, Raichu and Emolga. This is a problem though because if the best check to Jolteon is Jolteon itself, it makes games more dependent on stalling and speed ties, potentially warranting a ban.
Summary:
Jolteon has its flaws, but given the limited number of checks in UU, its niche in OU, and overall being a decently powerful Pokemon, I think it should be considered as either as OU or UUBL
UU->UUBLReasons:
1. Jolteon is tied for being the fastest non-mega Pokemon in the meta, while also having STAB-boosted Volt Switch for pivoting.
2. Jolteon's main rival for fast special pivot is Greninja, but Jolteon has a few things that make it unique. For one, Jolteon can counter opposing Greninja without needing to rely on a speed tie. It is also immune to paralysis and heals from Electric attacks, giving it sustain as well as a way to switch in safely. Jolteon's stats are mostly the same as Greninja except for one: while Greninja has a large attack stat that allows it to run mixed sets, Jolteon takes those points and puts them into special defense, which, combined with its lack of weaknesses, lets it survive some crucial damage, especially in the late game.
3. The main drawback of Jolteon is it's lack of coverage, meaning it almost always has to switch out against ground types in theory. I say "in theory" though because 3/4 of the OU ground types are weak to fairy, and Jolteon has access to Alluring Voice. With good prediction, a Choice Specs Jolteon can actually threaten a 2HKO into Garchomp, a 60% chance of an OHKO into Krookodile (100% with only 1 layer of spikes), and a guaranteed OHKO into Zygarde-10%. This leaves Excadrill as the only real counter to a late-game Jolteon sweep, but plenty of other Pokemon counter Excadrill very well.
4. From the UU side of things, Jolteon forms very strong cores with Pokemon like Mega-Drampa, Mega-Feraligatr, Shell-Smash Blastoise, and Clawitzer due to the fact that every ground type in UU is weak to water. Similarly, every grass type that resists Jolteon's STAB is weak to fire, meaning a well built team is very easily able to counter almost all of Jolteon's hard match ups. Jolteon instead is mostly checked by other electric types like opposing Jolteon, Raichu and Emolga. This is a problem though because if the best check to Jolteon is Jolteon itself, it makes games more dependent on stalling and speed ties, potentially warranting a ban.
Summary:
Jolteon has its flaws, but given the limited number of checks in UU, its niche in OU, and overall being a decently powerful Pokemon, I think it should be considered as either as OU or UUBL
