Berean Standard Bible (BSB)
When the two witnesses have finished their testimony, the beast that comes up from the Abyss will wage war with them, and will overpower and kill them.
World English Bible (WEB)
When they have finished their testimony, the beast that comes up out of the abyss will make war with them, and overcome them, and kill them.
Strong's King James
And{G2532} when{G3752} they shall have finished{G5055}{(G5661)} their{G846} testimony{G3141}, the beast{G2342} that ascendeth{G305}{(G5723)} out of{G1537} the bottomless pit{G12} shall make{G4160}{(G5692)} war{G4171} against{G3326} them{G846}, and{G2532} shall overcome{G3528}{(G5692)} them{G846}, and{G2532} kill{G615}{(G5692)} them{G846}.
The F.O.G *
(7) Whenever they have finished their testimony, the beast that comes up from the abyss will make war with them and conquer and kill them.
The F.O.G Message *
Young's Literal Translation
‘And when they may finish their testimony, the beast that is coming up out of the abyss shall make war with them, and overcome them, and kill them,