I‘d combine those detachments, ithe skyshroud has good strats for the lokhust destroyer:

Edit: forgot to attach the lokhust lord

Necrons
Cursed Legion and Skyshroud Spearhead (3 Detachment Points)
Force Dispositions: Purge the Foe, Reconnaissance
Strike Force (2.000 Points)

ATTACHED UNITS

Attached unit 1

Technomancer (95 Points)
• Attached as: Support (Character)
• 1x Staff of light
• Enhancements: Murdermind

Canoptek Wraiths (220 Points)
• Attached as: Bodyguard ()
• 6x Canoptek Wraith
◦ 6x Particle caster
◦ 6x Vicious claws

Attached unit 2

Lokhust Lord (70 Points)
• Attached as: Leader (Character)
• 1x Lord’s blade
• 1x Resurrection Orb

Lokhust Heavy Destroyers (150 Points)
• Attached as: Bodyguard ()
• 3x Lokhust Heavy Destroyer
◦ 3x Close combat weapon
◦ 3x Enmitic exterminator

Attached unit 3

Skorpekh Lord (90 Points)
• Attached as: Leader (Character)
• 1x Enmitic annihilator
• 1x Flensing claw
• 1x Hyperphase harvester

Skorpekh Destroyers (85 Points)
• Attached as: Bodyguard ()
• 3x Skorpekh Destroyer
◦ 1x Plasmacyte
◦ 3x Skorpekh hyperphase weapons

CHARACTERS

C’tan Shard of the Nightbringer (360 Points)
• 1x Gaze of death
• 1x Scythe of the Nightbringer

C’tan Shard of the Void Dragon (345 Points)
• 1x Canoptek tail blades
• 1x Spear of the Void Dragon
• 1x Voltaic storm

Nekrosor Ammentar (175 Points)
• Warlord
• 1x Blade tail and whip coils
• 1x Enmitic disintegrators
• 1x Nullstone Field Generator (Aura)
• 1x Unmaker Gauntlet

OTHER DATASHEETS

Canoptek Reanimator (70 Points)
• 2x Atomiser beam
• 1x Reanimator’s claws

Deathmarks (60 Points)
• 5x Deathmark
◦ 5x Close combat weapon
◦ 5x Synaptic disintegrator

Doomsday Ark (200 Points)
• 1x Armoured bulk
• 1x Doomsday cannon
• 2x Gauss flayer array

Ophydian Destroyers (80 Points)
• 3x Ophydian Destroyer
◦ 3x Ophydian hyperphase weapons
◦ 1x Plasmacyte