Multiple Arms

This creature has more than one pair of arms. The exact number of arms is indicated in parentheses (X), so a Genestealer with Multiple Arms (4) has four arms total.
It gains a +10 bonus on Athletics tests involving climbing and swimming.
In addition, for each full pair of arms it has (the Multiple Arms value divided by 2) it can make an additional attack as if wielding multiple melee weapons. In this case, the creature must either have natural weapons or actual melee weapons to wield for this to take effect.
Note that a creature still requires the Two-Weapon Wielder (Melee or Ranged) talent to make multiple attacks in the same turn.