With the old challengers coming back to the cash shop for the black friday sale, I was wondering which challengers I really should buy. May it be for the loot or the exp.

ping me please!^^

I too am looking for advice. I don't own any of the CS challengers, though I do have purchased copies of the Paintbrush Blades, Unstable Sample Syringe, and Aftershocks (from Sophie, Mutant Scientist, and Crithbolcan.) My pet can battle up through many Extremely Hard opponents.

and

Someone else just asked this in the main Battle thread, so I'll just copy and paste my reply...

To add to that - for loot on the CS challengers there may be some fairly expensive wearables and books, but it seems for the most part the value tends to be in the weapons and scrolls, and even then only once you start getting up in tiers. If you look through the achievement rewards, you can see those drops and price them.

Is there a list of loot drops for these anywhere?

Sorry, all I can think of is going to Subetalodge and searching by Challenger Loot rarity. For those older challengers who drop weapons, you can go to the achievements page and it'll show you what those are, but it doesn't show the rest of the loot they drop.

I'm still in the process of updating my Loot Guide after the reset. But I've got a link in it to the google spreadsheet that has more info. Loot Guide here but do note that it's quite image heavy!

That's awesome. Thanks!