Given that there are no limitations and no specific situations, Rudolf is the best, no contest.
* Vrest dash attack(hit multiple enemies).
* Easy stunlock infinite combos.
* 3rd highest mobility + beer + clones.
* D>A multishot injury bounce bug massively increases his damage for 1v1.
* Transform-specific combos & bugs.
* Transform allows him to scale to the level of his opponents while effectively being a better version of them(can escape being frozen for example), the lack of "DJA" from the moveset he steals from is a minor issue that only affects Julian/Henry.
If you don't count transform or beer though, I would consider Rudolf to be around #6 just because of his vrest dash attack but his full potential is otherwise kind of lackluster.
Would be boring if I just said Rudolf and moved on, so I'll go down the list:
2) Henry
Flute is overpowered due to its fast startup time & large AOE, and in low hp you can recover MP fast enough to use it again quickly. He can just run away and flute all the time - the only thing that can really pressure him against using this strat to its full power is chaseballs or an invisible Rudolf.
Without flute, he's still effective for crowd control due to his D>J critical shot, though for PvP tournaments he'd be considered low tier in HKC. Anyway only without flute he'd be around #5 - just give him room to run away & pixel-perfect controls and Henry can be untouchable.
3) Freeze
Ice Sword. Excellent zoning/crowd control and team synergy. Potentially infinite freezing combos mostly made possible by throwing the ice sword. His only real problem is fighting Julian because he can't freeze skulls and his non-whirlwind attacks aren't very good for breaking defense - but a skilled Freeze can still get around that. He's also a bit slow so he can't chase some of the faster characters, but eh.
4) Woody
He's a very versatile fighter by his own right without any glitches - there's a reason why he's considered top-tier in any LF2 1v1 tournament. He basically doesn't need mana for his combos, and even if you flipped his combos he can potentially reset the combo if correctly guessed your flips. While he's not the fastest char by raw movement speed, he is the most agile due to his ability to dash about rapidly & teleport. His moveset is very good for improvised team combos and his D>J Tiger Dash is a good crowd control. His only problem is that he's not particularly good against crowds compared to some of the other heroes, especially since he lacks a vrest dash attack, but even then he can be considered in the middle of the pack.
5) Deep
Fast vrest dash attack with a uniquely wide angle. Deep excels at punishing mistakes by his own right without exploits, has a leap to escape bad situations and his dash attack is actually what makes him so particularly good in crowd control. The main reason why I ranked him lower than Woody is because he is slow - you can outrun him easily, and also because he is a bit less team-combo-friendly than Woody overall (though he has some specific team combos that are much stronger than what Woody can do due to leap attack).
6) Firen
Burning people & specific burn combo exploits. This allows him to easily keep a big group of enemies downed, and less noticeably the burning lets him do massive combo damage either with his regular punching(groundfire punch/icesword) or with teammates(especially with Freeze - try Inferno + Icicle). What makes him lower on the list compared to Woody & Deep is primarily because the burning weakens his ability to cooperate with teammates and his tendency to burn himself. It doesn't help that his basic abilities are below average and his special moves cost quite a lot of mana and even HP for his explosion. It should also be noted that Firen is very effective against chars who rely on a lot of state 7 or Julian-style armor due to the flames hitlag-locking them, but this is a pretty rare situation.
7) John
John's ranking is the most debatable.
Energy Shield. The shield allows John to have a very powerful infinite combo, and on top of that its VERY effective for controlling the enemy AI - it makes them gather around John quite harmlessly and stops them from stealing weapons including milk. He'd basically be untouchable if he just stayed behind a shield all day and he's no slouch in 1v1, and he'd probably be the only character who can survive the last 10 waves of Survival without transforming(if he can even make it that far and not have Firzen crashing the game). The big problem is that his ability to ATTACK groups of enemies is very weak.
8) Davis
Dragon Punch. DP is what allows him to escape bad situations with an invulnerable counter, and his crowd control & team combo ability. Without it Davis can't do much against a crowd and only has good dueling skills.
9) Dennis
Dennis excels in duels largely due to his overpowered Grab combos with DvA or D>J along with chaseball spam. However, his crowd control & team synergy is absolutely abysmal, hence his low overall rank even though he is very much a high-tier character in 1v1.
10) Louis
Louis is simply way too slow & is plagued with a lot of negative bugs and his armor cannot make up for it. He is very reliant on his air thunder punch for crowd control, while for PvP he is more or less forced to make the enemy attack first before countering.
Do note this rank is strictly for Louis. If you count in LouisEX(which really should be considered another character on its own), he could be around #3 due to LEX's very high physical stats, instant jump attack and very overpowered rapidfire D>A airpush.
Bonus - this would be what the tiers would roughly look like for 1v1 in competitive settings(i.e. rules are in place like no milk/beer or no infinites):
1) Woody - there's very little you can do against his raw combo potential & effectively being able to dash attack twice in a row.
2) Deep, Dennis, Davis - they are very powerful melee fighters and relatively easy to use too.
3) John, Firen, Freeze - they aren't as easy to use as the Tier-2 guys, but they can be just as powerful in the right hands.
4) Henry & Rudolf - very reliant on your patience & mind-reading abilities.
5) Louis - he has very poor attack priority which makes it very hard for him to win.
* Vrest dash attack(hit multiple enemies).
* Easy stunlock infinite combos.
* 3rd highest mobility + beer + clones.
* D>A multishot injury bounce bug massively increases his damage for 1v1.
* Transform-specific combos & bugs.
* Transform allows him to scale to the level of his opponents while effectively being a better version of them(can escape being frozen for example), the lack of "DJA" from the moveset he steals from is a minor issue that only affects Julian/Henry.
If you don't count transform or beer though, I would consider Rudolf to be around #6 just because of his vrest dash attack but his full potential is otherwise kind of lackluster.
Would be boring if I just said Rudolf and moved on, so I'll go down the list:
2) Henry
Flute is overpowered due to its fast startup time & large AOE, and in low hp you can recover MP fast enough to use it again quickly. He can just run away and flute all the time - the only thing that can really pressure him against using this strat to its full power is chaseballs or an invisible Rudolf.
Without flute, he's still effective for crowd control due to his D>J critical shot, though for PvP tournaments he'd be considered low tier in HKC. Anyway only without flute he'd be around #5 - just give him room to run away & pixel-perfect controls and Henry can be untouchable.
3) Freeze
Ice Sword. Excellent zoning/crowd control and team synergy. Potentially infinite freezing combos mostly made possible by throwing the ice sword. His only real problem is fighting Julian because he can't freeze skulls and his non-whirlwind attacks aren't very good for breaking defense - but a skilled Freeze can still get around that. He's also a bit slow so he can't chase some of the faster characters, but eh.
4) Woody
He's a very versatile fighter by his own right without any glitches - there's a reason why he's considered top-tier in any LF2 1v1 tournament. He basically doesn't need mana for his combos, and even if you flipped his combos he can potentially reset the combo if correctly guessed your flips. While he's not the fastest char by raw movement speed, he is the most agile due to his ability to dash about rapidly & teleport. His moveset is very good for improvised team combos and his D>J Tiger Dash is a good crowd control. His only problem is that he's not particularly good against crowds compared to some of the other heroes, especially since he lacks a vrest dash attack, but even then he can be considered in the middle of the pack.
5) Deep
Fast vrest dash attack with a uniquely wide angle. Deep excels at punishing mistakes by his own right without exploits, has a leap to escape bad situations and his dash attack is actually what makes him so particularly good in crowd control. The main reason why I ranked him lower than Woody is because he is slow - you can outrun him easily, and also because he is a bit less team-combo-friendly than Woody overall (though he has some specific team combos that are much stronger than what Woody can do due to leap attack).
6) Firen
Burning people & specific burn combo exploits. This allows him to easily keep a big group of enemies downed, and less noticeably the burning lets him do massive combo damage either with his regular punching(groundfire punch/icesword) or with teammates(especially with Freeze - try Inferno + Icicle). What makes him lower on the list compared to Woody & Deep is primarily because the burning weakens his ability to cooperate with teammates and his tendency to burn himself. It doesn't help that his basic abilities are below average and his special moves cost quite a lot of mana and even HP for his explosion. It should also be noted that Firen is very effective against chars who rely on a lot of state 7 or Julian-style armor due to the flames hitlag-locking them, but this is a pretty rare situation.
7) John
John's ranking is the most debatable.
Energy Shield. The shield allows John to have a very powerful infinite combo, and on top of that its VERY effective for controlling the enemy AI - it makes them gather around John quite harmlessly and stops them from stealing weapons including milk. He'd basically be untouchable if he just stayed behind a shield all day and he's no slouch in 1v1, and he'd probably be the only character who can survive the last 10 waves of Survival without transforming(if he can even make it that far and not have Firzen crashing the game). The big problem is that his ability to ATTACK groups of enemies is very weak.
8) Davis
Dragon Punch. DP is what allows him to escape bad situations with an invulnerable counter, and his crowd control & team combo ability. Without it Davis can't do much against a crowd and only has good dueling skills.
9) Dennis
Dennis excels in duels largely due to his overpowered Grab combos with DvA or D>J along with chaseball spam. However, his crowd control & team synergy is absolutely abysmal, hence his low overall rank even though he is very much a high-tier character in 1v1.
10) Louis
Louis is simply way too slow & is plagued with a lot of negative bugs and his armor cannot make up for it. He is very reliant on his air thunder punch for crowd control, while for PvP he is more or less forced to make the enemy attack first before countering.
Do note this rank is strictly for Louis. If you count in LouisEX(which really should be considered another character on its own), he could be around #3 due to LEX's very high physical stats, instant jump attack and very overpowered rapidfire D>A airpush.
Bonus - this would be what the tiers would roughly look like for 1v1 in competitive settings(i.e. rules are in place like no milk/beer or no infinites):
1) Woody - there's very little you can do against his raw combo potential & effectively being able to dash attack twice in a row.
2) Deep, Dennis, Davis - they are very powerful melee fighters and relatively easy to use too.
3) John, Firen, Freeze - they aren't as easy to use as the Tier-2 guys, but they can be just as powerful in the right hands.
4) Henry & Rudolf - very reliant on your patience & mind-reading abilities.
5) Louis - he has very poor attack priority which makes it very hard for him to win.
~Spy_The_Man1993~
Steiner v3.00 (outdated), Challenge Stage v1.51
Luigi's Easier Data-Editor, A-Man's Sprite Mirrorer
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