So i never did the 2 star be more objective and tower defense challenges. I went back around level 17 to try and do them and I never got anywhere close to the end. Then I hear people talking about how they got it on their first try and that they didn't know why people were failing so bad. Well what I noticed about all of the videos where people were beating it with little opposition was that they were almost always a new character.

So I made a brand new character and sure as [censored] first try I nail every single 2 star objective with 5-7 plus minutes to spare.

I hope this is a bug, cus bots scaling with your level in challenges is stupid.

If you don't believe me, try using a level 20 to beat the 2 or even 3 star objectives. Then use a new character, you'll see the difference.

This seems to be true because I was getting pummeled on the Escort 3-star challenge as a level 12. Didn't even come close to completing it, maybe made it 20% of the way on 3 different tries.
The question I have is....if you complete the challenges with a new character, does your ranked up character have access to those unlocks??

Any time you unlock a weapon or attachment, it's unlocked for all characters present and future.