Hello everyone. Fitting with the changes to Nemesis Days, I decided to make a tier list featuring all Nemesis monsters so that players who want to get them can more easily decide, making a very short analysis on their roles as well. Keep in mind that these are my opinions and that I would appreciate it if you gave me constructive criticism instead of just stating that I'm wrong. Also keep in mind that Nemesis monsters are strong in general and that any one Nemesis you pick from here is at least above average in their element. This list is relative between Nemeses, also the placing of monsters in most tiers is important.
The list will not feature the "weaker" versions of Nemeses, unless they do different things than their upgraded versions (like Hydratila), since one has no reason to deliberately get a weaker monster.

S-Tier: Reserved for the best Nemeses, this tier features monsters that are cornerstones of the metagame and will likely be relevant for the foreseeable future. This is the only tier in which a monster's position does not matter.

-Samael the Plague Carrier/Samael the Fever Scatterer: We are starting off the list with the former king of Monster Legends. When Samael was first released, people- with good reason -called him a pay to win button. He is among the most versatile monsters in the game and has some of the most impressive status effects as well. His moveset features a lot of buff/debuff control moves, an extremely strong turn transfer move (Plague Carrier's costs 0 Stamina too) and up to 2 revival skills, plus he has the Bulwark trait, one of the best traits a monster can have nowadays. Definitely one of the best supports, if not the best support, in the game as of writing.

-Llum the Magical Matriarch: Besides Samael, Llum is the only other Nemesis with the Bulwark trait. This Llum ranks higher than her other form, Iron Leader, because she's faster and has an AOE Stun, which makes her infinitely better as a support. Like Samael, Llum has tons of buff/debuff control skills like Accepted Fate, a move that removes all buffs from all enemies and gives them Damage Reduction + Blind, and Battlefield Speech, a move that removes all debuffs from all allies and gives them Double Damage + Precision. Doubling as one of the best deniers and supports in the game, Llum is definitely a pivotal member in the current meta.

-Xiron the Ruby: Ruby's prowess at denying is so great that he can be compared to even Warmaster Thalassa, who is the best monster in the game, and this shows how threatening he can be. This form in particular is extremely deadly as he has an AOE that inflicts Ignite and 2 random control effects to all enemies, which almost guarantees their denial, and what's better is the fact that random denials include Mega deny effects as well, and you'll definitely see them a lot when you use this monster. Tying with Llum the Magical Matriarch in Speed, Ruby is one of the best Nemeses and one of the best monsters in the game in general.

A-Tier: This tier includes monsters that are definitely strong, but their power levels are clearly not on the level of the S-Tiers. Even if they're not as strong as the S-Tier, a monster from this tier can and will be a deciding factor in battles.

-Llum the Iron Leader: Iron Leader tries to be an attacker, as evident by the powers of her Metal skills, but her Base Strength falls short for this task. However, her support moves, like the ones I listed on Magical Matriarch, and Bulwark as a trait are still there, which secures her place at the top of the A-Tier. An excellent support monster.

-Faraday the Discharger: Introducing the Anticipation mechanic in the game, Faraday is an impressive attacker that also has Tough as his trait. This form is the best Faraday form because of his access to Stun and Earth attacks, which makes him strong against his own element and most notably against Zyla and VoltaiK. Stun is especially important since it allows Faraday to more effectively disrupt the opponent's turn transferring. Besides form specific advantages, all Faradays have nuclear damage outputs that makes them unable to be ignored easily and Anticipation, which throws a wrench in the opponent's plans with great ease.

-Faraday the Obscure: In terms of raw damage, this Faraday is the most powerful. Despite his lack of deny (or deny-like) effects, this one can apply Poison and Bleed at the same time, and stacking this with Sunburn can have deadly results. However, Anticipation and deny have wonderful synergy, and lack of this synergy hurts Obscure.

-Talos the Island Protector: The only Artifact Nemesis, Talos has the highest damage output of all Nemesis monsters. He also has Trait Disable moves which are always appreciated. This form of Talos has AOE Sunburn, one of the best Torture effects in the game, and does more damage against Metal monsters which helps in Metal and Mechanical Wars. However, you need to be mindful of Stamina, as Talos consumes a lot of it.

-Xiron the Emerald: Lost beneath the great shadow of Xiron the Ruby, Emerald has a massive power gap between him and said monster. His exclusive moves are much, MUCH weaker than Ruby's, with Emerald's applying Poison and Stun, while Ruby's applying Ignite and 2 random deny effects. This leaves Emerald as just an above average denier. Still, he has the powerful things all Xirons have, like the trait, nice Speed and a diverse range of deny effects.

-Talos the Forgotten Artifact: This Talos, while powerful, definitely got the short end of the stick compared to Island Protector - Sunburn vs Poison is not even worthy of an argument. Still, his damage output is respectable, plus his single target Nature move uses Hacked, an exclusive Possession, meaning it goes through Possession Immunity.

-Faraday the Electrolyzer: This form has access to a Total Blind move to somewhat interrupt extra turn passing, plus he has a 100% Accuracy AOE Blind, which is useful for making status effects land difficult. However, the disparity between this form's and the others' stats is simply too great to ignore, making him the worst Faraday form.

B-Tier: This tier's members are monsters that are more powerful than your average monster, and with minimal help from teammates, can put in great work.

-Hydratila the Riftmaker: Hydratila is definitely far from being a pushover. He is an excellent attacker thanks to his Thetys moves costing 0 Stamina and having 0 CD while giving his team Stamina Regeneration, making it excellent against Stamina Control monsters like Wangzhou. He also has an AOE 0 CD buff removal which is extremely important in the current metagame. This form, with his access to 2 separate deny effects, is the best form of Hydratila thanks to that and his good Strength making him the best attacker out of his three forms. The thing that gives him a spot in B-Tier instead of A-Tier is his trait which is lacking for a Nemesis monster, with others above him all having some sort of Hardened form - Xiron the Emerald's place above him is proof for this, because Riftmaker's moveset is better than said monster's.

-Hydratila the Boltcaster: Since he's a Hydratila, this form also has Riftmaker's utility moves, but his Stuns are replaced with Dazes which, while definitely a downgrade most of the time, can actually become more useful sometimes. However, the lack of 2 deny forms and a noticeable drop in Strength cannot be ignored, hence why he ranks below said form.

-Warthak the Sunbringer/Warthak the Mountainsplitter: Warthak's Control Immunity is priceless as an attacker, and he has some utility with buff removal as well. Warthak has great attacking moves, such as a single target Base 80 Stun with Sunburn or Bleeding and a 100% accurate Base 45 AOE. These forms share the same spot because while one has power vs. Earth monsters and greater Speed, the other has Sunburn and greater Strength.

-Hydratila the Icebringer: Despite his notable power against General Thetys compared to his other forms, said monster is not nearly as relevant as she used to be back in the day, which makes Icebringer slower and weaker than his two other forms. Having Freeze as his only debuff is also not too good since Recently Frozen is a buff that exists. Still, Area Unblessed and Thetys moves keep even this form above a certain threshold that allows one to recognize him as an impressive monster.

C-Tier: Monsters in this tier need more help from teammates than those in the B-Tier, but can put in great work like them too. Despite being the lowest tier, keep in mind the inherent power of Nemesis monsters while viewing the monsters in this tier.

-Lucifire the Hopefreezer: Lucifire's damage output is very impressive, and this form's Water attacks can devastate many members of the Dragon Book and Fire element, which is a huge boon for any attacker. With AOE buff removal and single target Freeze attacks, this form can adapt to the flow of battle easily too. What keeps her down here is her downright unimpressive trait for a monster of her caliber - if she had a Hardened variant, she would definitely be ranked higher.

-Lucifire the Helltaser: This form follows very closely behind Hopefreezer, and in fact her much more comfortable Speed tier of 3465 plus her Stun in place of Freeze might make her more useful than the latter in certain matchups.

-Nadiel the Pyromancer: Nadiel's power level is simply too low when compared to the other members of this list, which is why he's here. Still, this monster has very respectable Torture effects, like Reverse Healing, Burn and Ignite in one move - Reverse Healing is very useful against the omnipresent healing Relics such as Healing Mask, while the other two speak for themselves. Tough as his trait, along with Burn, Freeze and Ignite Immunity, is also very helpful.

-Nadiel the Deforestator: The single reason why this form isn't left out like other "weaker" forms is because of the AOE he learns at Rank 3, which removes buffs from all enemies, something the other two forms don't have.

-Nadiel the Flooder: Ladies and gentlemen, I present to you, the worst elemental weapon wielding Nemesis. Flooder has nothing to set himself apart from good traditional deniers, and while that might sound like it's in a weird place between an insult and a compliment, being in such a spot is bad for Nemesis monsters, who are expected to be better than just good. If you are going to get a Nemesis, they must have something not many other monsters have, and that's something Flooder lacks.