5-8% Strength for 4.5s on Kill. Stacks 5 times.
Up to 5-20% Strength based on the charge time of your heavy attacks. Stacks 3 times.
Hitting an enemy with the special attack gives them 10-16 stacks of 2.5% Brittleness. Debuff lasts for 5 seconds and can have a maximum of 16 stacks.
5-8% Strength for every 10% of magazine spent during continuous fire. Stacks 5 times.
Krourk IV has some fun combos and unique interactions with abilities and weapons. The heavies have extremely short windup and delay times which makes attack speed work well with them and also makes Thrust start charging very early into the attack, just like Karsolas.
It has two single target lights after its single target heavy attack, making a pretty strong solo combo.
For crowd control you can do fast Heavy + Light combo for low density enemies, hold the heavy for high density, or use push attack + light + heavy or push attack + heavy for controlling packs of ragers or elites mixed into a horde.
Unstoppable Force blessing is actually a viable alternative to Slaughterer and quite a bit of fun. It requires holding your heavies until they go off on their own which is a bit longer than thrust's timer, but it gives infinite cleave targets, including against crushers and other armored enemies that normally stop your attacks from cleaving. Your damage is still affected by hit mass so you won't do much damage past the first ~3 armored or ~7 unarmored targets but will apply full stagger and bleed in the weapons' full attack range.
Single Target Combo examples:
Heavy 1 + Light + Light
Heavy 1 + Uppercut + Light + Light
Ripper Bayonet + Light + Light + Heavy 1
Light + Light + Uppercut
Push attack + Uppercut + Heavy or Light combo (for reliable stagger)
Crusher kill combo: Bayonet + 2 unbraced volleys OR 1 unbraced volley + 2-3 stabs
Multi Target Combos:
Push Attack + Heavy 2 + Light
Heavy 2 + Light
Ripper Bayonet (important target) + Heavy 2