As a stamblade which monster set would be the best one to use?

[kbm demon.♡]

1. Molag Kena
(1 items) Adds 129 Weapon Damage and Spell Damage
(2 items) When you deal damage with 2 consecutive Light Attacks you trigger Overkill for 6 seconds, which increases your Weapon and Spell Damage by 516 but also increases the cost of your abilities by 20%.

2. Velidreth
(1 items) Adds 129 Weapon Damage (2 items) When you deal damage, you have a 20% chance to spawn 3 disease spores in front of you after 1 second that deal 10320 Disease Damage to the first enemy hit. This effect can occur once every 9 seconds.

3. Balorgh
(1 item) Adds 129 Weapon Damage
(1 item) Adds 129 Spell Damage
(2 items) When you use an Ultimate ability, you gain Weapon Damage and Spell Damage for 10 seconds equal to twice the amount of total Ultimate consumed.

4. Slimecraw
(1 items) Adds 833 Weapon Critical
(1 items) Adds 833 Spell Critical
(2 items) Gain Minor Berserk at all times, increasing your damage done by 8%.

[Count Smashula]

Probably velidreth or stormfist.

[Brownstone]

You can gain Minor Berserk from a Nightblade skill so Slimecraw is the worst option.

[Trigger]

1pc Kena + 1pc Velidreth for 2 x 129 WD or 2pc Kena for big boost of DPS or 2pc Velidreth for 3 poison balls.

[Prodigy]

5. Selene
1 item: Adds 1096 Maximum Stamina
2 items: When you deal direct melee damage, you have a 15% chance to call on a primal spirit that mauls the closest enemy in front of you after 1.3 seconds for 12000 Physical damage. This effect can occur once every 4 seconds.

[Midnight]

velidreth. stormfist and selene are also good

[Soul2506]

Velidreth or selene

[Requimatic]

Velidreth is the default choice, with Stormfist coming in as a very close second; and actually pulling ahead in some situations. (Blackrose Arena, for example.)

Outside of those, Kra'gh is still a solid choice, and Selene's is good as well.