Since i am bored, Im going to being powerscaling The characters and stuff. Alright at our First place of weakest character, is LV 1 frisk, There health got demolished by flowey, so considerably without any armor they are weak sauce.
Asriel(Normal state.): Asriel, in there Normal state after chara fallen, Asriel is only a Kid, but i believe they could handle them self, But other then that They are weak.
Chara(Normal state.):Again this state Of chara, is a child, and couldn't really do much, But could bring up a good fight, if they wanted to.
Sans: sans with no KR is weak as hell, They would only do one Damage Through out a battle, but however we cannot ignore the KR, when you are lv 19 they do alot of damage, KR is karmic retribution And It works if you have done sins The damage increases, so it depends on how many sins you done, But sans is lazy, and only has 1 defense, So one hit and sans is dead, so sans
Alphys: Alphy's is weak, But there technology could be used in battle, but would not have much confidence And would probably freak out, and flee before you could even do an option.
Flowey: Flowey, Could probably Make any character struggle, If they do a surprise attack like they did in The true pacifist, They often use trickery to gain the upper hand, like they did with papyrus in true pacifist telling them the numbers of all the monsters, And how they killed asgore when asgore was low, if you spared them, So Flowey Could Probably kill some Kids, and a Lazy skeleton, And lets not forget with the Determination and before frisk's fall Flowey wouldve been a mountain level, considering they killed every monster When they had power like Saving and loading, So flowey Before frisk fall is mountain level, But after frisk Fall, They aren't so strong.
Other monsters: The non boss monsters, are Weak, But can put up a decent fight if you don't know What to do.
Alright now we go into the boss Monsters, The monsters that are one of the strongest in the under ground.
Papyrus: Papyrus, as stated has Brought up a Hell of a fight against Undyne, but his kindness Can get him killed, like in genocide route, But papyrus if you remove the kindness From him, Would be higher up on this list.
Toriel: Toriel, I know died from a toy knife and a lv 4 or lv 5 Child, But I believe because she let her Guard down something similar to that, And lets not forget If she wasn't Merciful for humans, You would've died, And toriel would've not hold back, and lets not forget she is the queen of the underground, And She is able to Send flowey flying, and asgore if she wanted to, So she is Strong, But lets go higher up on the list.
Mettaton: Mettaton in there normal form is Considerably Unkillable, but when there switch Is flipped, Toriel, Could bring up a good fight, but Undyne Would Defeat Mettaton in this state.
Undyne: Undyne, is Considerably One of the strongest, Considering she can bring up a good fight against asgore, And has been Trained by the king himself, So undyne With that Is one of the strongest, but not stronger then these new Opponents!
Asgore: Asgore, is the king of the monsters, And he is Mountain level atleast, Considering That he was able to take hits from lv 20 Frisk, Twice So that is certainly an impressive feat, in durability, And since a human could kill the entire Underground and such, and considering he has killed 6, Some were Pacifist some were not, So Asgore is One of the strongest in the underground, And against Frisk, he mostly is Possibly not trying as He is Filled with grief, and guilt And doesn't even look Frisk in the eyes, But The next monsters put that to Shame.
LV 20 frisk: LV 20 frisk, is Considerably one of the strongest, They are definetly a mountain level, maybe even more They killed asgore with relative ease two shotting, and killed flowey easily which isn't to impressive, They have killed Everyone in the underground, So they are in the top 5 of the Strongest beings, in the under ground, but are put to shame By our next characters!
Godly like beings These beings are unstoppable.
W.D gaster: W.D gaster has 66666 Stats, and cannot be stopped after the core accident.
Omega flowey: Omega flowey, Is one of the strongest, with the power of 6 human souls, they overpower frisk with Determination, and can load and save files, And put the human in a constant death loop, if they wanted to They could kill frisk permanetly, But if the human souls Rebel against omega flowey, i believe we all know what happens next, If omega flowey was somehow defeated, they Would just load a file and be at Full health, This battle would be impossible If the human souls did not rebel against flowey.
Asriel(With all the souls): Asriel in there Hyper death state, is By all accounts unkillable, And undefeatable, Unless you do a save button move, But other then that Asriel, could easily Destroy the universe if they wanted to, and probably the multiverse, So Asriel is in the top 2 with all the souls in the underground, and in there hyper death.
Chara: Chara, Is The strongest character in Undertale, in there true form they are Stats which is truly terrifying, Chara at the end of the Genocide route, Destroys the entire Reality, and probably destroyed the Universe, They are the Physical embodiment of stats, if they wanted to, They probably could destroy the multiverse, And they are able to one shot LV 20 frisk, With What is Thought as Infinite damage, The slash destroyed the reality with relative ease, So Chara is the Strongest Character due to this.
Also, i will not be adding The annoying dog to this list, as it is obvious were they would be placed, and the other creators, so uh hoped you enjoyed this list i guess.