[The Horror in the Shadows]

Holy inscriptions:any chaos/traitor/renegade model in base-to-base combat with the marine has a -1 Ld
Weighted stock: the marine gains +1str. on the charge in additon to any other rule but always strikes at int3, due to the weight of the bolter. may not be used with anti-grav plates
Damaged/old/badly maintained: the model with the bolter is 3pts cheaper, but the bolter now suffers from 'gets hot' rule
Zarthax poison round:single-use only. wounds on a 3+ and causes D3 wounds Ap-. only avaible to ICs and sergents due to highly toxic nature (kills space marines just as easy as the normal humans)

Anti-grav plates: bolter becomes assault 2 weapon but because of its weightlessness and fear on of losing his bolter (and the rare tech.) in the heat of battle, the marine only gets 1 attack in close combat reguardless of other rules(e.g. charging). May only be used with the scions of mars trait due the rareness of the tech.