I'm trying to make a mythic version of Ygorl, Lord of Entropy, but have run into a bit of an issue. It may just be user error on my part in some way, but the "Is mythic?" check box is grayed out and doesn't appear to be working. The same thing happens if I uncheck the "is legendary?" box, it goes grey and won't allow me to re apply it, but it works just fine so long as I don't uncheck it first. any advice?

Hello,

So i'm struggling to mark a creature as legendary. I can not check the box for it, yet I can check the box for lair actions. I am using the template for a storm giant, so would that have anything to do with it?

Not an error on your part. I'm having the same issue myself with made from scratch monster. Also waiting on a fix for this.

Both options appear grayed out in the creation screen. Here's a screenshot with the lair description as a comparison, which is clickable:

I encounter the same issue, which ruins a few of my plans, i hope we get an explanation and a solution soon

When using "Werewolf" or "Kiril Stoyanovich" as template for the monster creator, Legendary and Mythic can't be toggled (see screenshot below).

https://imgur.com/a/tpbbt1i

EDIT: After checking with the "create from scratch" option, I have noticed that the option "Legendary" and "Mythic" can't be toggled once toggled off or if they haven't been selected when the creature is created.

I also have this issue

I'm having the same problem trying to create from scratch a mythic monster.

I am as well.

As a work around, if you use a creature with existing Legendary actions as the template you can edit the Legendary actions to suit your monster.  A bit of extra work to edit everything from the template to your homebrew but it starts with the Legendary box checked.  Just don't uncheck it because it will grey out.

https://www.dndbeyond.com/monsters/1228759-test-creature-w-legendary

Not sure if this is allowed - please tell me if it not :),, and I don't recommend pasting commands/scripts from strangers of the internet in your console. But I got the same problem and figured out that removing the disabled flag from the checkboxes enables them. If you press F12 on the homebrew monster page and paste this in the console, the checkboxes should be clickable again.

$(".ddb-homebrew-create-form-fields-item-input").removeClass('disabled');

 It seems the code responsible for deactivating the textfield is unintendedly also disabling the checkbox... I hope this workaround helps

Also having this same issue...Sorry, I don't have any extra input, I'm just lurking to see if there is a fix to this soon...

Have a related problem. Created a monster for our campaign that have Legendary Actions but it also include Mythic Action in the final stat block despite not checking the Mythic Action block. Have tried it twice creating it from scratch with the same result. Gonna make a new later but try to use another creature with Legendary Actions as a template instead. 

EDIT: Tried again and now I managed to make it work. Just have to remove the sample text from the text boxes of the ability that is not gonna be used. Unchecking the checkboxes does nothing if there is text in the text box with that ability. 

Quote from LeSchnitz >>

Not sure if this is allowed - please tell me if it not :),, and I don't recommend pasting commands/scripts from strangers of the internet in your console. But I got the same problem and figured out that removing the disabled flag from the checkboxes enables them. If you press F12 on the homebrew monster page and paste this in the console, the checkboxes should be clickable again.

$(".ddb-homebrew-create-form-fields-item-input").removeClass('disabled');

 It seems the code responsible for deactivating the textfield is unintendedly also disabling the checkbox... I hope this workaround helps

 This worked for me, thank you! Still weird that the issue is happening though.

Quote from LeSchnitz >>

Not sure if this is allowed - please tell me if it not :),, and I don't recommend pasting commands/scripts from strangers of the internet in your console. But I got the same problem and figured out that removing the disabled flag from the checkboxes enables them. If you press F12 on the homebrew monster page and paste this in the console, the checkboxes should be clickable again.

$(".ddb-homebrew-create-form-fields-item-input").removeClass('disabled');

 It seems the code responsible for deactivating the textfield is unintendedly also disabling the checkbox... I hope this workaround helps

 That worked, thanks!

Also had this problem, also found that solution above to work

I instead opened the Inspect Element window, found the checkbox, and deleted its "class" attribute. Saving the thing worked fine.

Thanks!