I was able to complete the Unstoppable Challenger mission in Battle Villa and thought I’d share in case anyone found it helpful! I’m not a free to play player, but even for me this felt like a daunting task going in. However, it turned out to not be so bad.
I’ve only included some of the more interesting battles I had, but hopefully this helps you get a feel for how to approach this. Make sure to choose Vitality Treats at each chance you get; I was pretty stingy with them, but you’ll definitely want to save up in the early rounds. Enjoy!