Win all Challenges is an optional mission in Up Your Arsenal, taking place in the Annihilation Nation, Station Q9. After winning the Tyhrra-Guise from the first couple of challenges, Ratchet and Clank decided to compete in more Annihilation Nation challenges to earn bolt prizes, eventually culminating in the final challenge, the "Qwarktastic Battle".
After "Win the Tyhrra-Guise", you can complete eight additional arena challenges, culminating in the "Championship Bout", and three additional gauntlets. The remaining challenges cannot yet be completed until returning for the mission "Meet with Courtney Gears", after which, all challenges can be completed, with the exception of some limited weapon challenges such as "Chop Chop" which require weapons not yet available. Weapon restriction challenges are required to beat the mission.
The final arena challenge, the "Qwarktastic Battle", is only available when all previous arena challenges leading up to "Championship Bout" and "Championship Bout II" are complete. Completing this challenge earns 200,000 bolts. Though it can be completed straight after "Championship Bout II", and thus straight after "Meet with Courtney Gears", it is best to instead wait to return later with much better weapons and armor.
Completing all challenges will reward you with the Annihilation Nation Champion trophy for the Starship Phoenix trophy room. This means completing all leading up to the "Qwarktastic Battle", as well as all weapon restriction challenges.