If able to, Nekaph must always issue and accept challenges. When fighting in a challenge, Nekaph gains a Ward Save (5+), and his Killing Blow will take effect on any To Wound rolls of 5+.
Source: Warhammer Armies Project: Unofficial 9th Edition (v2.2)
If able to, Nekaph must always issue and accept challenges. When fighting in a challenge, Nekaph gains a Ward Save (5+), and his Killing Blow will take effect on any To Wound rolls of 5+.