Yes good idea but i have 3 islands to do

[silent minnow]

Can try a spline, right click it and select prefab and add the rocks to it

Use the vector tool to make a spline, then left click it in the hierarchy tab and click on prefabgenerator.
Inside prefabgenerator you can add embankments prefab

[ruby island]

I've already tried but it doesn't work on my end.

[silent minnow]

Search my name and you will see @dawn pasture explain it with pictures

[ruby island]

I've seen it but it's for small hills+

[green hamlet]

If you want to use objects to do it you will most likely have to place them by hand for them to look good, but that will take a lot of time.
You could make a generator that just places the cliff objects in a row, but I never saw a version of that approach that looked ok. Mostly because of the repatition and the cliffs being perfectly vertical.
And don't scale cliff objects to far, because their collider does not match the lod0 perfectly, so there will be some clipping issues at some point.

If you have large area to cover you could also try using 2-3 custom surface materials and just make the cliffs with your surface geometry.
Blud showed that approach some years ago: #enfusion_terrain message

[idle moon]

its finding the custom materials thats the problem. we have no tutorials on how to actually MAKE them at the moment from scratch

[green hamlet]

• Take a look at an already existing terrain material and what textures it uses
• Find texture you have the right to online (or make your own, which is a whole other story)
• Look at https://community.bistudio.com/wiki/Arma_Reforger:Textures and see what texture goes on what channel. (e.g. BCR = Albedo, Albedo, Albedo, Roughness).
• Use photo editing software or easier Quixel Mixer or if you have it substance to put the online texture in to the right channel and image formats (see the wiki link).
• Import
• Profit

[idle moon]

yeah its the making them yourself that I want to do lol