I'm finding this challenger REALLY annoying. It keeps stealing all my weapons, which obviously puts a crimp in my plans to beat it.

I'm using my T11 pet Skitter, whose stats are: Health: 2660 / 2660 Strength: 2050 Defense: 2020 Speed: 2031 AP: 77

I have these freezers/blasters/healers: And these weapons: + Parched Baguette Crystal x 4 + Critical Strike Tear Crystal x 3 + Critical Strike Tear Crystal x 1 and Parched Baguette Crystal x 3 Scrolls:

My strategy is to use the Intricate Energized Helmet + Soma Tablets on my first turn, then switch to freezing with my scrolls and blasting/attacking. This has worked once, but the vast majority of the time everything just gets stolen. Any tips on better weapons/mod crystals or better strategies for dealing with this guy? I have the AP to add a few more scrolls and a fair bit of SP for item upgrades.

Cassowary More freeze spells would help. He can't steal from you while frozen. Cheaper way to prevent stealing (and freezing) is Blessing on Natural Armor (BONA) mods. When active they prevent stealing for 3 turns. They are in the battle token shop.

My pet has similar stats and I've gotten 7 wins. I believe I'm maxed out now with my arsenal. I had mostly parched baguettes as mods, but I did have BONA, as mentioned above, in one slot on each main weapon. This worked until about 6 wins. Then I discovered that I was using my freezing scrolls too soon. Try to do some damage without the scrolls until you've brought him down a bit, then chain freeze him while you knock the rest of his health. I hope you're able to use this method to get more wins! Good luck!