seriously stuck on ep3 offline (hunter)

[Shadamoo]

Use the A.Beast/Dark killer cards that double damage done to that monster.

1.5 times the damage

Well, this is Sighting 4, and yes, I do hate this mission also. I wouldnt use Kranz, I would take them on with Sif'ler, because her high ATP and ability to use Cross Slay and Round Slay, so the bastardish monsters dont hurt you as much, because you can take more than one of them at a time.
Use the best Saber/Sword weapons you can so you can get biggest hits as possible.

Alternatively, use Kranz+ 3x Handgun + 1x Mechgun + 1x Crush Bullet = A lot of damage! Then, use the Crush Bullet + Split Boost/Beat/A heavy hitting card = A lot of damage to 4 squares enemies!