This is about as "Pure" as Death Guard builds get. You'll see why.
++Purge Detachment++
-Chaos Lord w/ Mark of Nurgle on Bike, w/ Fist and Claw & Sigil of Corruption - 150
-5 Chosen w/ Mark of Nurgle & 4 Plasma Guns - 165
-5 Chosen w/ Mark of Nurgle & 4 Plasma Guns - 165
-5 Havocs w/ Mark of Nurgle & 4 Autocannons - 130
-5 Havocs w/ Mark of Nurgle & 4 Missile Launchers - 150
-5 Havocs w/ Mark of Nurgle & 4 Missile Launchers - 150
++Purge Detachment++
-Chaos Lord w/ Mark of Nurgle on Bike, w/ Fist and Claw & Sigil of Corruption - 150
-5 Chosen w/ Mark of Nurgle & 4 Plasma Guns - 165
-5 Chosen w/ Mark of Nurgle & 4 Plasma Guns - 165
-5 Havocs w/ Mark of Nurgle & 4 Autocannons - 130
-5 Havocs w/ Mark of Nurgle & 4 Missile Launchers - 150
-5 Havocs w/ Mark of Nurgle & 4 Missile Launchers - 150
Total: 1850
You don't have Obsec, but you're a wall of unyielding T5 FNP, with enough dakka to make most armies blush. Some Havoc units took Missile Launchers instead of Autocannons to use Chem rockets, or threaten 3+ save units at range (force more Jinks, pop some Crisis Suits, etc).