Two Point Campus

One other option for anyone who has already three stared the campus is to go into sandbox mode to complete this.

Choose basically any map and make sure you choose Creative mode. Schedule as many matches as you can against Jumbo and you should get this easily in the first year.

This achievement can be obtained in Fluffborough. This achievement can potentially be obtained in three ways.

At the start of the level you'll watch your students get humiliated by Jumbo team which will give you one unmissable loss. The other 4 are yours to grab.

1. Play the game naturally
As soon as you get full control send a challenge to Smogley Salamanders. Your students will be low leveled and if you do this fast enough they won't be able to beat the opponent.

After that's done, focus on upgrading your university and making sure you earn some money. As soon as you get all your rooms done and staff hired at the beginning of year 2, start challenging next teams. I was able to beat everyone until Flemington Flobtrotters.

You should challenge Flemington until they can be beaten by you 100% of the time. I was actually able to grab only one win against them but fortunately there is the Jumbo team that should be challenging even for well developped universities.

2. Farm losses after 3 stars
If you end your level with 3 stars and you still haven't got this achievement, you'll have to farm it at the beginning of each academical year. Your 3rd year students will be the weakest around September as they still haven't got a lot of progress during their 3rd year and should be closer to level 14, not 17. You can probably grab a loss or two each year.

Alternatively just remove your highest ranked students so your weaker guys will be forced to play. This should give Jumbo a big advantage that you won't cover.

3. Potential cheese method
Unfortunately I got this idea way after finishing the level but as you get one loss at the beginning you could theoretically start the level, lose the match, restart and repeat it 4 more times which will give you this achievement.

As soon as you start your first year you will be tasked to play a team. Schedule it and play it and you will lose. Right after that game schedule more matches against the first opponent you can play, I was able to schedule 4 more games for the year. Depending on rng, you will hopefully lose most of those, If not don’t worry, start year two and schedule more games against the next opponent and you should unlock it. I upgraded my campus to level 2, and was required to build a second field. With the second field you should have more than enough matches between both fields to lose the remaining games.