J'avo will get ready and try to charge towards player. He will attack two times while charging. The first one will just stun the player and the second one will knock the player. It can be countered. There is also a different dash attack version if his legs are mutated into noga-let which cannot be countered.
Quick Scythe Attack
When the player is very close to the J'avo, it will do a quick attack that can stun the player. Note that if he has two mutated arms, he will strike twice. It can be countered if his legs aren't mutated into Noga-Skakanje.
When he has low health (there are some exceptions), he will raise his arm and try to knock the player with it. It does heavy damage so be careful. Note that if he has two mutated arms, he will strike twice. It can be countered. He will also do a similar attack when player is lying on ground although difference is this one cannot be countered and he will only slam once.
Unlike many other J'avo mutants, Ruka-Srp do not possess any specific weak points.
Shooting or meleeing them in the head will stun them for a bit, allowing you to perform coup de grace on them. Although shooting may cause a head mutation, meleeing is always safe.
They are less affected by flash grenades so be careful.
They are hardly stunned by bodyshots so if you wanna shoot them from body to prevent head mutation, use shotguns or sniper rifles.
They also get up much slower, so stomping them is more easier when compared to other J'avo.
If one arm is mutated, its highly possible either its head or other arm can be mutated when damaged enough. Aim for the legs, its a safe bet.
Ruka-Srp can be found in all Chris chapters but 2; Jake Chapters 3-4 and Ada Chapters 1 and 3.