So my group is doing a 1 shot and the dm told us to bring a maxed out character to the table. I was thinking a fighter rogue combo but I'm open to suggestions. He gave us 50,000 gp to spend however and our choice of 1 uncommon 2 rare and 2 very rare OR 1 uncommon 2 rare and 1 legendary. Help me become the ultimate fighter.

Step 1: Define your goals.  What do you want your character to be optimized for?  Melee combat?  Ranged combat?  Stealth?  Skills?  Languages?  Senses?  Defenses?  Conning people? 

Melee preferably it's pretty much just a brawl session.

whatever you may want , i suggest a ring of spell storing

allows ANY spell up to 5 level to be inside the ring from any class and retains the stats of the original caster, if applicable so you can pump that full of anything you might need and it does not need to be 5th level , could just be 4 an 1 or 5 first level slot (theoretically you could hold your action to absorb a spell, but thats honestly up to dm not any rules)

a potion of speed is good also , non concentration haste for a minute ? GIMME

potion of growth as well

my personal preference would be fighter, eldritch knight

battle master has only  5 dice, and is more of a support in my eyes

eldritch knights get at level 20

4 first level spells (absorb elements, shield are a must have, maybe cromatic orb)

3 second level spells(blur gives disadvantage on attacks, )

hold person, if they fail their wisdom saving throw, the paralysis condition states that all attacks within five feet, are crits, as a fighter level 20 you get 4

NOTE

you are most certainly gonna get a barbarian i feel, specialy a bear totem, why dont you surprise him with shadow blade? 2d8 (psychic) PER HIT WITH MODIFIERS AND THROWABLE 3D8 if cast with 3rd levels slots

3 third level spells only thing i can think at the top of my head is haste, or slow which is the exact opposite of haste

1 fourth level spell, fire shield, dimension door, ottos sphere are great ones too

you can attack as a bonus action after a cantrip, ,which determening what cantrips you choose is great, and thisworks with ranged weapons

give disadvantage on resisting your spell saves,(you might want to give some points to inteligence, 7 ability improvements helps, and i doubt you will need charisma

can cast a spell and attack with bonus action(disadvantage to savingthrows apply)

and a 30 foot teleport with actionsurge, before ore after, as long as you use it 

you need to read the class details for a better understanding, BUT REMEMBER 2 THINGS

1you are a fighter with some magic, dont compare yourself to a druid or wizard

Talk to your dm if it seems to restrictive, nothing changes powerwise with the abjuration , evocation replacement,

hell even removing spell resticrtions might be better

and have fun

Thanks those are some really great options I appreciate it.

step 2

KNOW THY ENEMY

do you have an idea what the others might play?

this will definitley help.

also 50,000 gold , but only a few magic items?

can you clarify?

moar items

you coud dump con or int if you pic up a headband of intelect or a periptact of wound closure as both raise a stat to 19 regardless of base

you could also get a cloak of displacement

disadvantage to hit you every turn

but if you are hit it is spent for the round

shouldnt be a problen with a plus 5 to ac from shield and does not requre concentration

but i thnk it vanishes with saving throw dammage too

I'm working on building an EK for the next campaign my group is playing, starting at first level. We're already over six months late starting, but such is life. My main reason is to get those mobility spells, long strider, misty step, action surge teleport, I'm sure there are a few items that can augment this even further. Plus you have nice AOE spells for lower level mobs, like say a small goblin army. Between you and the wizard tossing fireballs or walls of fire or whatever mobs will be nice and roasted. 

Plus us the weapon bindis nice, being able to instantly summon your weapon to your hand so your never unarmed is a wonderful thing! Though champion and battle master have definite bonuses, I always like mixing magic because it's magic :) personal preference. Otherwise I'd suggest a champion, don't they get a continuous health regain ability? Ultimate tanks! Plus improved critical ranges don't they?

oh, well if you  want an adventures Eldritch knight  for a campain, my recomendation s to talk to your dm for what ever you may feel is best really, multiple people online discussed the change on the spell selection, hell even on sage advice say that the school restriction on the eldritch knight is flavor,

and dont forget you can create scrolls and magic items with the abilty to cast spells

i hope ou get to play soon!

My DM has a lot of cool flavor stuff for EK, which is converted from 5e. It is the only class that can learn the spell Chanel ability, though that's elf duskblade" not EK, which is a learned skill if you have a teacher. Though the elves have been hunting down non elf mages, especially EK's so that could be a fun issue to deal with (I already know this going in, so I'm ok with the risk). Were also using gritty setting, so one week is a long rest. In my DMs world that's ten days. Ten days to get spells back. BUT WAIT, there is a way to get an arcane recovery ability or learn new spells or even expand spell slots. I think he said something about jumping into a magic mode and interacting with the weave directly, and trying not to get ******* murdered by arcane monsters that may likely try to steal my connection to the weave. But I could end up with higher spell slots, more spell slots or arcane recovery, oh the gambles I plan on taking :)

What you should do is make a human battle master noble background, because you get a horse(5e). With your money, you can pay for armor of the horse. Then use a sword and a shield. Use the dueling fighting style. Then spend your legendary item on a vorpal long sword. Overpowered. Buy some plate armor, or use your magic items on magic armor. Get a non-magical heavy crossbow. Then, with all this combined, you'll be a level 20 human warrior on a horse with an orange long sword charging into battle.

However do not take this class for a god. He has it's weaknesses. My favorite fighter ever was a level 1-20 human battle master noble that used a glaive (a long stick with a sharp end), and he got plenty of magic items from dungeons to boost him. At level 17, the party deemed him as a god. Then we fought a solar. I almost died. Everyone else did (save the wizard, who abandoned us mid fight)

Max out armor class

but in an all out brawl, their will be spell casters so you have to focus savingthrows too or you will get trashed instantly