For DBC you cant check to see if limbs are colliding, only if objects are colliding.
So, to solve your problem, i suggest you check to see if the objects are colliding (the character with the monster) and also check the animation frame (to see if the sword swinging animation is being played) that way, you can "kill the monster" when the objects collide only when the charater is swinging its sword.
this is just whipped up in a few seconds... hope it helpes...
`Character Object number is 1
`Monster Object number is 2
`Sword swinging animation is from frame 20 to frame 40
If Object Collision(1,2) = 1 And Object Frame(1) > 20 And Object Frame(1) < 40
Delete Object 2
Endif
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