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Gemling Legionnaire

CoC Gemling: Infinite Comets

Community build by NickTew (full guide on Mobalytics ↗) · 0.5 Runes of Aldur · updated 2026-07-08

The “0-cost CoC” Gemling: a Spark caster built on a Mercenary chassis that freezes the whole screen and converts those freezes into free, automatic Comets. Insane clear on a starter budget, and it scales into one of the fastest blink-spam mappers in the game.

S
mapping tier (community)
<20 div
working start budget
1 button
playstyle while mapping
+8
power charges via swap

The concept (why it works)

Three pieces interlock:

  • gives multiplicative damage per Power Charge you consume, and makes all of your damage count toward applying every elemental ailment. A weapon-swap trick banks up to +8 Power Charges before you start blasting.
  • The Gemling node Advanced Thaumaturgy is abused through Frost Wall quality (increased ice-crystal life). Frost Wall level and HP are scaled, then the Verglas support in Spark converts that into 200-250%+ gained as extra Cold damage. Verglas does not care which skill breaks the wall: a stray Comet popping it still buffs your Spark.
  • With that much cold, Spark freezes everything nearly instantly, which feeds Cast on Elemental Ailment enormous energy even on a budget: it fires Comet + Living Bomb (Spell Cascade) for free, endlessly. Frost Wall itself sits in a Cast on Critical setup so the walls spawn and break automatically. No Archmage needed, so mana stays comfortable.

How it plays

  1. Map start: cast Frost Bomb (3 elemental infusions), consume them with Firestorm to generate charges. Repeat twice → 8 Power Charges (top-left of your screen).
  2. Weapon-swap by pressing Spark, then hit the Pinnacle of Power buff on your bar: a huge damage steroid that lasts about a minute (sometimes doubled by Heightened Charges). Refresh it when it drops.
  3. While mapping, Siphon Elements keeps you flooded with infusions: usually one Firestorm press instantly re-caps your charges, no Frost Bomb needed.
  4. Then it is a one-button build: hold Spark and watch the screen freeze, shatter and rain Comets.
Buff management is the whole skill ceiling
The only real learning curve is keeping Pinnacle of Power up and getting used to Adonia's Ego charge rhythm. Everything else is automated by the CoC / Cast on Elemental Ailment setups.

Gear priorities

  • (check trade): aim for 20% quality, +1 maximum Power Charge, +3 levels and at least one socket.
  • (check trade): runemastered for Ward, ideally 2 sockets and max crit chance.
  • (body-armour variant): socket Fox Idol + Rune of the Blossom, with 80%+ increased effect of socketed items (the 9%-quality breakpoint).
  • Belt: until you can afford (check trade). Ingenuity's spare Spirit also enables Explosive Transmutation.
  • Rares: NickTew optimises for 70%+ Item Rarity minimum across the gear; all resistance rolls are interchangeable, so drop rarity pieces if the price stings.

Skill setups (mid-budget reference)

SkillSupportsRole
(lvl 19) · · · · The one button. Freezes via Verglas cold gain.
· · · · The payoff: free Comets on every freeze.
· · · · Automates wall spawn/break for Verglas.
(lvl 20) · · · Self-cast copy; walls also deal real damage.
· · The ~1-minute damage steroid.
(19) · · Infusion engine while mapping.
+ / / / Charge generation rotation (weapon set 2).
Utilities · · · Charges, res, mana, extra clear.

Support requirements: Str 40 / Dex 25 / Int 125. Import the exact variant (tree included) from the Mobalytics build planner export.

Strengths
  • Insane damage and clear speed for the cost.
  • Genuinely cheap to start (sub-20-div variant) and works out of the gate.
  • No Archmage: mana feels comfortable from day one.
  • Scales into blink-spam Temporalis endgame.
Weaknesses
  • Adonia's Ego charge rhythm takes getting used to.
  • Squishy before Headhunter money.
  • The buff (Pinnacle of Power) must be refreshed every minute or so.

Variants & campaign picks

The guide ships five gear/tree variants in progression order, each with its own equipment, gems and passive-tree import (grab the exact one from the Mobalytics build-planner export):

1 · Turbo Budget

The sub-20-div entry point. Fewer omen-of-light-tier rolls, but the core loop (charges → Verglas → CoEA Comets) already works.

2 · Mid Budget

The reference used on this page: proper Adonia's Ego roll, runemastered Maligaro's, rarity-optimised rares.

3 · Blink Spam $$$

The imported high-budget mapper: Headhunter online, blink-spam movement, screen-wide clear.

4 · Blink Spam (GPU friendly)

Same power, tuned to melt the screen without melting your framerate.

5 · Temporalis + Fork WIP

The experimental endgame: blink with Fork projectiles. Marked work-in-progress by the author.

Notable campaign reward picks
  • Act 3 Venom Draught: 25% increased Mana Regeneration Rate.
  • Abandoned Prison: 30% increased Mana Recovery from Flasks.
  • Interlude Tabana's Pillar: 12% increased Cooldown Recovery Rate (feeds the CoC loops).
  • Act 2 Medallion: +1 Charm Slot. Halls of the Dead: resistance tests as needed.
Verify in-game
This is a living community build (NickTew updates it frequently, and the Temporalis variant is marked WIP). Cross-check the Mobalytics page for the latest gem levels, tree imports and variant gear before committing currency.

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