Self-damage on melee attack ?

So, I am working on a little mod, mostly for me and some friends.
I was trying to re-balance spino, Rex and Gigant. One of the change was to give them all the hability to damage stone-tiered structures. That was the easy part. The second idea was to add self-damage in the same way as when human harvest wood without any tool, but here fore when they hit a stone structure. Here, I am stuck. I’ve been trying to look into the harvesting sections of the SDK, but I can’t find anything related to those self-damage.

My question is : can we add self-damage to a custum harvest or attack ? And if the answer is yes, does someone know how to do ?

Pretty sure that would need to or can be achieved with a graph. I’m still a noob with UE4 but I do remember seeing several nodes that can add damage to an eventhandler. I’m guessing it should work similar to the graphs from this post where WoefulMacabre helped me with some graphs. Dino-specific-damage-from-a-projectile-Is-it-possible I’m sure there is a way to tweak it and achieve the results you want using the damage causer.