Endgame aircraft
Ace Combat 8 X-40 Nightmare Unlock Guide
Quick answer
The X-40 Nightmare is the endgame stealth superfighter with UAVs/railgun tech. Buy from the Aircraft Tree after campaign gates and enough MRP. Strong Ace S-rank generalist; Mission 29 features an X-40 ace.
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Why use it
- High-value target deletion with limited special ammo
- Post-stall capable
- Swap to AoE attackers on ground-cluster maps
Unlock
Progress campaign, earn MRP, purchase after fighter prerequisites (often F-22A/F-35C/Su-57 path). Check in-hangar price.
People also ask
Unlock X-40?
Aircraft Tree after endgame gates + MRP.
Best plane?
Often late-game yes; not always for ground AoE.
Mission 29?
Selene uses X-40.
Further reading
Related guides
Best Aircraft · MRP · Aircraft Tree · Mission 29
Primary: Ace Combat 8 X-40. Also: X-40 Nightmare, X40. Independent fan guide.