Best Plasma Launcher Build in Abyssus

Tier SPatch 1.3.62817The Blazing WeaponAoE ceiling / room deleter
Patch 1.3.62817 quick answer

Best Plasma Launcher build at a glance

The Plasma Launcher is an arena-control weapon first and a boss weapon second. Build a dependable explosion pattern, use Frozen to create distance, then repair the single-target gap with the ability and charm slots.

Primary fire
Flak Cannon
Secondary fire
Void Infusion
Aspect
Frozen (Frost)
Weapon Forge
Explosive Valve · Accelerating Core · Bouncy Core
Ability
Smiting Spear

Fires explosive plasma orbs that detonate on impact. Area damage, extra projectiles, and control can turn it into excellent room clear, while isolated targets remain the main weakness.

Best for: Spawner rooms & dense packs (weak vs single bosses)

Want to tune this setup?Primary and secondary modes, Aspect, weapon Forge upgrades, ability and Charms are preselected from this guide.
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How to make the build work

  1. Use the Void Infusion secondary mode to group enemies before adding more explosion area.
  2. Fire from range so Accelerating Core has room to grow and self-damage is less likely.
  3. Use Frozen to create a safe follow-up shot, then add Smiting Spear and Giant Slayer for bosses.

Solo, co-op and boss adjustments

Solo route

Kite around the edge and fire into the centre of a pack. The launcher is safer when enemies move into a prepared blast than when you retreat while shooting at your feet.

Co-op role

Ask the frontline player to hold enemies inside your grouped area. Your job is to erase spawns and objectives, not compete with a Revolver on one exposed weakpoint.

Boss plan

Use a Frozen control window to land deliberate shots, then keep Smiting Spear on the isolated target. Do not rely on splash alone; use the most direct projectile path and keep enough distance for Accelerating Core.

Common mistakes

  • Firing point-blank while using distance scaling
  • Stacking area size after the existing blast already covers the pack
  • Entering late Depths without a single-target charm or ability

Depth 30 variant

Its weakness is boss single-target — use the Frozen route to create safe damage windows and Smiting Spear to keep direct pressure on the boss.

Plasma Launcher fire modes

Choose one Primary and one Secondary fire mode at the Workbench. “Recommended” marks this guide’s editorial selection.

Primary fire

  • Semi-automatic — Explosive plasma orbs.
  • Flak CannonRecommended — Fast plasma orbs.
  • Seekers — Hold to lock targets, release a barrage of orbs.

Secondary fire

  • Disintegration Beam — Piercing beam of plasma.
  • Void InfusionRecommended — Creates a black hole that damages and slows.
  • Adhesive Compound — Sticks to a target and explodes repeatedly.

Plasma Launcher Ancient Forge upgrades

These are weapon-specific Ancient Forge upgrades, not generic stat priorities. “Recommended” is an editorial pick for this route.

  • Seismic Fuel — Hitting 3 enemies increases the explosion radius for 5 sec.
  • Molotov Fuel — Enemies take 50% continuous weapon damage for 5 sec. after being hit.
  • Revolving Valve — Lasting attacks have doubled duration, charged attacks have halved buildup.
  • Explosive ValveRecommended — Damage now scales with the projectile's explosion radius.
  • Accelerating CoreRecommended — Explosions increase in size the further the projectile travels. Up to 100%.
  • Bouncy CoreRecommended — Projectiles bounce 2 times or until an enemy is directly hit, exploding each bounce and dealing 25% more damage.
  • Spreading Heat — Hitting an enemy suffering from status effects or that are Stunned, Slowed or Frozen deals the same damage to a nearby enemy.
  • Repeating Blasts — Plasma Launcher explosions have a 60% chance of triggering again. Additional explosions can also trigger again, but have a 20% decreased chance per explosion.

How to unlock the Plasma Launcher

Reach the Royal Abyss within 45 minutes. From its starting building, turn right instead of left and jump → dash → jump across the dark chasm to the hidden-room altar; after 45 minutes the entrance is sealed.

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Patch and source notes

Official baseline: Abyssus 1.3.62817, released. This page was impact-reviewed on. Read the official hotfix feed.

Hotfix 1.3.62817 fixed the Seekers progress indicator; this guide recommends Flak Cannon and no Plasma balance-value change was documented.

Fire mode, ability and weapon Forge names are reference facts; the selected combination is an editorial recommendation.Names and taxonomy reviewed; legacy effect values are not all independently re-tested. Check the in-game Logbook for a live numeric value, browse the Forge catalogue, and see our methodology for the review policy.

Choose the alternative that best addresses this build’s trade-off.