I Am The Hero

Ok the annoying part of this one isn't actually fighting to level 50 but actually having the game not crash on you getting there. I've been to level 49 about 8 times now and it always crashes there. I can tell you that the windows 10 version is worse about crashing in the later levels but it is surprisingly easier then on the xbox one. In the later fights theres times on xbox one where you will fight 3 yes 3 bosses at the same time. On win 10 version its only 2. Its also just easier. Now on to the solution:

You are going to want to play through the campaign for some of the other achievements but more importantly there's one character we need unlocked. Hes the guy in the green coat with hood.

Now enter workshop fight mode- Your going to need green coat to beat wave 50. So once you load in, your strategy will be to get as many hits as possible without hopefully getting knocked down and losing your counter. The earlier levels will be the trickiest because you have to plan well. What I did was use the main character as much as possible to get his blue power bar filled, then swapped to green coat and left him in. I used green coat guy to fight all battles and my main character to fight bosses with. The green guy moves sooo fast hes not too good with the bosses when you can get some awesome punch combos in with your main character to maximize damage. Towards the end of the bosses health bar they will use their power ability that makes their combos unbreakable so do the same to save your health.nIt will be important to keep both of your characters blue bars up (activate with your right stick). Your combos will be unbreakable.
Your method of fighting : The key to this is the green guy and using the forward forward punch (x) combo followed up by mashing the punch (x button)in hopes of getting critical punches in for instant deaths. Repeat this process back and forth across the screen. In the later levels you will pretty much be permanent blue bar powered. You can turn it off by swapping characters between fights and back using your right bumper. Try not to lose your combo. Pick up as many sodas and food as you can to stay healthy.

The later levels will start having monsters that leave green power bars laying around that makes your damage go through the roof especially when using your power bar. Try to leave some on the ground until the last moment before they go away to time in order to start new waves with max damage or for when your tasked with 3 bosses at the same time.
After boss fights try and choose powerups that enhance your blue bar ability and chances such as these (I will star my favorites try to get them ASAP)-

*Headphones- more blue energy gained*
*Shopping cart- enemys drop more health and powerups (sodas etc.)*
*Helmet- actions are not easily interrupted*
*Anonymous drink- increases critical judge distance*
Batterypack- beat faster (faster attack combo)

Theres one that maxes the blue bar and your health bar too I cant remember the name of them but they will be useful too.

Keep playing and you will get it. The later levels surprisingly get alot easier with the correct power ups chosen and correct method as writen. Now hopefully your game wont crash or freeze. Thats the worst part... Like doing halo ODST back in the day.

This is just a few extra tips to help with this god awful annoying achievement. Juicyjams guide is good and hopefully these extra steps will make it a bit more bearable.
I did this ach on xbox 1 so you dont need to have a win 10 device/pc.
Be patient, take a break and try another day. The reason i say this is because this was my last ach and took 10-12 hours over 1-2 hours attempts over a week or so. Ok now MY tips:
Use green hooded guy as 2nd character.
ALWAYS at the start/end of wave stand to far LEFT of the screen, this should stop the odd enemy appearing just right off screen which you CANT kill and you will have to restart. Some enemies will still get stuck left side of screen but they CAN be killed for some reason, on wave 45 one of the 3 bosses got stuck there making it easier.
Every 5 waves you get a boss until wave 40 when you get 2 and 45 and 50 you get 2 or even 3.
After every boss wave up to 40 you get a choice of 3 power ups. Shopping cart, annoymous drink are ESSENTIAL before wave 26, if you dont have them consider restarting, trust me you WILL need health pick ups! After that get bananas, headphones, helmet, brass knuckles and battery pack if you see them. Spring and rollerskates were useless to me.
NEVER EVER let either character die! You cannot turn off rage if you only have 1 character.
I used green coat 90% of time even on bosses except the flying boss unless i had low health then swap out!
ALWAYS try and kill the big hip hop dancers and black hooded enemies quick the frogs/knives destroy the frame rate to a crawl!
Keep health as high as poss and you should be fine till wave 26-30.
Now wave 26 or maybe 31 stay to left at start/end of wave and click right stick and mash left or right and x and hope you slowly kill stuff cos the frame rate will be horrendous from now on (except the boss waves) until you have 4-5 enemies left. Press rb to end rage change character and rb to switch back. Repeat until 50 and hope the game doesnt screw you over.
If you health bar is going down quick CHANGE character, there is hothing worse than getting in the 40's n screwing it up cos you got greedy, once you have 2-3 enemies left you can change back if theres health to pick up.
Lastly good luck, its do able but one of the worst achs ive ever done because of this modes piss poor frame rate!