Testament frontman Chuck Billy
supplied the guest vocals for this track. Exodus singer Steve "Zetro" Souza
said: "Chuck and I have known each other forever. We work really well together; we know each other really well. So if I'm doing my vocals and he's there, I can trust him to go, 'No way, Zet, [it] doesn't sound good like that. Do it like this,' or, 'Yeah, that's killer.' If he says it sounds killer, I know it is."