Here's an answer that takes the current known information a little further, with some suggestions for what might need to be done next...
Stanza 1:
As @Dmihawk found (since confirmed by the OP), the answer to this stanza is:
MINUS
I am one of four brothers, we make a foundation
in some way we are native to every nation
if one is kind, the other is not
if one is a little the other is a lot
from what you give i will take
only 1 of my brothers will moreso break
As a brief summary of @Dmihawk's logic, the 'four brothers' here are the four basic mathematical operations: addition, subtraction, multiplication and division, universal in mathematics around the world. The later lines refer to the opposing natures of addition/subtraction and of multiplication/division (interpreting being 'kind' and 'giving' as increasing a number) and 'break' here referring to division having an invalid result when attempting to divide a number by 0.
Stanza 2:
This stanza clues:
TARTARUS
where to find the long lost party?
of those once high, yet became naughty
swallowed like a black like whole
In Greek mythology, Tartarus is the deep abyss used as a dungeon of torment and suffering for the wicked, and as the prison for the Titans. The Titans were the gods who came before the Olympians, ultimately defeated by Zeus and banished from the upper world ('once high') and imprisoned in Tartarus.
wants your time, not your soul
In contrast to many depictions of underworlds, many of the punishments inflicted in Tartarus were not intended as physical torture but as permanent frustrations - for example, King Tantalus's punishment in Tartarus was to stand beneath a fruit tree with low branches which bent out of reach every time he attempted to pick the fruit, and by a pool of water which receded from him every time he tried to quench his thirst.
sounds like the armor of your mouth
after water is burnt, it tis more south
Tartarus contains the sound of 'Tartar', which is a hard deposit that crusts around teeth ('the armor of your mouth'). (I am unsure as to the precise relevance of the final line of the stanza here...)
Hint 2: Is there a place for a King of Sissies? And with his cat?
This is a further reference, cluing:
King Sisyphus (a soundalike of sorts for 'King Sissy' + 'Puss'), who spent his time in Tartarus forever rolling a rock to the top of the hill, only for it to roll back down to the bottom again every time.
Stanza 3:
This stanza clues:
US
you yes you it is always true
but me yes me, it shall also be
then what is made when you are with me?
is that 1 plus 1 or is it 3?
You and me together can be described as 'we' or 'us'. In fact, no matter how many people are involved in the 'you' here (which can be plural as well as singular) - whether just 2, or 3, or even more - collectively the group can still be referred to as 'us'.
The answer (a theory):
At this point we need to combine the words we have found using the arithmetic operations in between them - i.e. add the first to the second, then remove the letters of the third. Doing this gives us something like:
MINUS + TARTARUS - US = MINUSTARTAR (or perhaps even MINTARTAR, removing 'US' from both words...)
It is difficult at this stage to know exactly how we are supposed to proceed, but here are two lines of thought assuming that MINUSTARTAR is the intended way to process the words we have found...
1. If we need to interpret this as another 'soundalike', we can feasibly make this '"MINOR" STARTER'. With the mention of astronomy in the puzzle, this might be a wordplay clue for the word 'URSA' (given that Ursa Minor is a famous constellation). We then need to find a 'prancer' (commonly another word for a horse) who has competed under a name with connections to bears (since ursa = bear in Latin); there are several of these on record and I can find no way of identifying one that is a more satisfactory fit for the puzzle than any other. (Note I am leaning away from somebody named 'Ursa' itself, since this is usually a female name in Eastern Europe, which disagrees with the gender pronouns in the stanza here.)
2. Another possible (though slightly more twisted) 'soundalike' for 'MINUSTARTAR' is 'MINER'S DAUGHTER'. With the additional 'Oh!' before {answer} in the puzzle, this might suggest a reference to the folk song Oh My Darling, Clementine, in which Clementine is the name of the daughter of 'a miner forty-niner'. We would then need to repeat our hunt for a famous racehorse or athlete under the name of Clementine. However, so far this search is also yet to bear any fruit (badum, badum!).
Still searching for a satisfying final answer, but I feel this has made decent progress, solving the 3 initial stanzas at the very least...
