Im currently playing on "deepmoblearning-refabricated-0.5.12-BETA+1.19.2" as it is what the server(aof6 na server) has.

First of all, it was so frustrating to set the trial ground, cuz it wouldn't tell me the size and most of the search results were very outdated. Eventually I found out it was 2121. But this also didn't work so I built an additional ring, making it a 2323 which finally worked. I guess it just needs and additional ring for something.
Another problem is that, just slightly going on to that last layer fails the trial immediately and you lose your key.
So I hope you could somehow ease(?) the trial fail conditions... Or maybe just allow us to build a wall around the trial so that we don't have to worry about slipping beyond the boundaries. Or even a timer that allows us to stay out of the boundary for a few sec before having to return

Originally we had the wall requirement because mobs could throw you outside the area, instantly failing the trial. We've had a knockback-to-trial feature for a while, so it's sensible to remove the wall requirement, I'll see what I can do about it on dev 👍🏼

I hope you could at least get the key back... 2diamonds and a whole mob grinding gone in a second cuz u stepped on a line is pretty... yeah.... Or maybe I just didn't understand how to play the trial, like strategy wise... But anyhoo I wish it gets a bit loosened up in out of range-wise 😆 2023년 9월 5일 (화) 오전 1:51, Luiz Feikes @.>님이 작성:
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Originally we had the wall requirement because mobs could throw you outside the area, instantly failing the trial. We've had a knockback-to-trial feature for a while, so it's sensible to remove the wall requirement, I'll see what I can do about it on dev 👍🏼 — Reply to this email directly, view it on GitHub <#140 (comment)>, or unsubscribe https://github.com/notifications/unsubscribe-auth/BCK547JF4EPDJJYSYNL53ZTXYYBIZANCNFSM6AAAAAA4KRDGLE . You are receiving this because you authored the thread.Message ID: @. com>

As long as trialKeyReturnIfSucceed is true, you'll get your key back if you succeed at the trial. Otherwise, you can ask the server owners if they can set trialKeyConsume to false.

Just wanted to add to this - I almost uninstalled the mod because I could not figure out how to get the arena set up. I see in config it says radius 12, but even with a proper circle it would not register the arena as valid. I ended up just disabling that in the config.

No idea why mine didn't register. It looked like I was the invalid block preventing it from registering (flames were spawned on my character and followed me around). Really awful mechanic, I think it should be removed or at least make disabled the default.

For what I know, the arena is square shaped, although if you made it in a circle it would be bigger than a square..
Or have u maybe tried increasing the size?
I dont know which sizes u would have tried but something like 25x25 square?
I think the default was about a 21x21 square

It was a circle. From the wiki, and a recent video I saw, this seems to be the intended shape. Plus it says radius, which applies to a circle.

I did try increasing and decreasing the size, adding walls, etc. Nothing I tried worked, hence almost uninstalling. Disabling the check worked for me, though.

Edit: Thanks for the note about the square. I re-enabled the validity check and redid the arena to a 25x25 square and now it works correctly. So, the wiki needs to be updated. It specifically says, and illustrates, a circle here: https://github.com/CafeteriaGuild/DeepMobLearning-Refabricated/wiki/2.-Tutorial:-Trials

You can see I made my arena like the wiki explains here:

But as aoshibba said, and as I verified, it has to be a square.

I'm glad it worked!!

FIxed on dev branch, update fixing it should be out by tomorrow. For the current release, make sure these 4 blocks at the keystone's level are air and it should work: