Randomising between the legal abilities

[Fortree_Lover]

I'm playing through Pokemon Black with random eggs in the boxes and I have had no problem randomsing the IVs and Natures of the eggs to be hatched but I can't seem to randomise the ability number for the eggs. 

When I randomise the IVs and Natures I use these instructions: 

.IV_ATK=$0,31
.IV_DEF=$0,31
.IV_HP=$0,31
.IV_SPA=$0,31
.IV_SPD=$0,31
.IV_SPE=$0,31
.Nature=$0,24

I have tried similar instructions for ability number but have had no results, I have tried these variations of this instruction:

.AbilityNumber=$0,2

.AbilityNumber=$0,$2

.AbilityNumber=$0,$1,$2

I can use the ability number to set it to a particular ability like this .AbilityNumber=$X where X is the ability number but as soon as I include the range in the same way that I did for the IVs it says it has modified the files but nothing actually changes.

Has anyone managed to do anything like this or can point me in the direction of where I might be going wrong?

Thanks for any help you can provide

[Kaphotics]

You'll want to run a multi-step batch edit (using the `;` character on a line to indicate the break between instruction sets).

1. Randomize a value (like Nature) to 0-2.
2. If (nature) is 0, .AbilityNumber=$0
3. If (nature) is 1, .AbilityNumber=$1
4. If (nature) is 2, .AbilityNumber=$2
5. Randomize the donor value (Nature) back to whatever you want.

[Fortree_Lover]

On 6/9/2025 at 3:12 PM, Kaphotics said:

You'll want to run a multi-step batch edit (using the `;` character on a line to indicate the break between instruction sets).

1. Randomize a value (like Nature) to 0-2.
2. If (nature) is 0, .AbilityNumber=$0
3. If (nature) is 1, .AbilityNumber=$1
4. If (nature) is 2, .AbilityNumber=$2
5. Randomize the donor value (Nature) back to whatever you want.

Thanks so much for your help, I did eventually get it working by setting the Ability dependent on box position then randomising the boxes after doing the abilities and it's fine in game when they hatch but after evoloving they revert to their original abilities. Is there any way to prevent this?

[Kaphotics]

1 hour ago, Fortree_Lover said:

Thanks so much for your help, I did eventually get it working by setting the Ability dependent on box position then randomising the boxes after doing the abilities and it's fine in game when they hatch but after evoloving they revert to their original abilities. Is there any way to prevent this?

Not without patching the ROM to disable the updating of abilities on evolution. There isn't a patch like that for any game as far as I know.

[Fortree_Lover]

On 6/12/2025 at 7:01 PM, Kaphotics said:

Not without patching the ROM to disable the updating of abilities on evolution. There isn't a patch like that for any game as far as I know.

Thanks I figured as much