MewGenius Answerbook Risk: High

Rat King Boss Guide

Safest opener, biggest mistakes, and the cleanest way to beat Rat King in Mewgenics.

HP 100 MV 2

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Fast answer

Read this first

Main idea

Remove the first wave of adds immediately; don’t let the board fill.

Biggest mistakes

Letting adds accumulate: spawns snowball tempo and block escape lanes.
Standing adjacent carelessly: Toss converts adjacency into collision damage.

Winning line

You stabilize spawns early (kill priority adds before they overwhelm lanes).
You keep adjacency discipline to deny easy Toss value.

Before you start

Quick-scan notes before you commit to the fight.

Quick scan

Safest opener

Remove the first wave of adds immediately; don’t let the board fill.
Respect trample lines and do not let your backline sit directly behind your frontline.
Kill or contain spawns early before the fight snowballs.

Bring / avoid

Bring: AOE or efficient cleanup
Avoid: Single-target-only damage with no cleanup
If notes are partially unverified, assume the worst-case version until confirmed in-game.

Fight plan

The safest way to approach the fight without reading a wall of text.

Decision-first notes

Win conditions

You stabilize spawns early (kill priority adds before they overwhelm lanes). You keep adjacency discipline to deny easy Toss value. You plan for the enrage breakpoint and enter it with board control.

Opener

Remove the first wave of adds immediately; don’t let the board fill.

Midfight

Pressure while managing spawns; keep spacing to reduce Toss setups.

Finisher

Before enrage or when it starts, spend defensives and end quickly; don’t fight enraged + full adds.

Detailed notes

Positioning, run killers, and loadout reminders.

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Run killers

Letting adds accumulate: spawns snowball tempo and block escape lanes.
Standing adjacent carelessly: Toss converts adjacency into collision damage.
Ignoring buff turns: Drink Booze can turn a manageable boss into an evasion/crit spike.

Positioning rules

Avoid adjacency unless you’re committing to a controlled trade; Toss is the tax.
Keep the board open: leave at least one retreat lane that spawns can’t block.
If he buffs, respond with tempo (burst or control) instead of slow trades.

Loadout hints

AOE or efficient cleanup

Single-target-only damage with no cleanup

Source: boss-chp2.csv · Last tested: 2026-03-02 · Some move values are still being confirmed in live runs.

Detailed notes

Mechanics, background notes, extra item links, and deeper context.

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About Rat King

Add-spawning trample boss with throws; control the board or get swarmed.

Type: Boss

Mechanics snapshot

Main mechanics

Trample Summon/Spawn Throw Enrage Self-Buff

Key triggers

Spawns adds and escalates Enrage around ~70 HP (per notes)

Moves to know

Spawn Rats

Spawns 2 Lil' Rats (per notes).

Spawn Fleas

Spawns 2 Fleas adjacent (per notes).

Drink Booze

Heals ~5; gains crit/dodge and damage/spd buffs; then throws bottle for ~5 ranged damage (range unverified).

Dash

Straight line dash dealing ~10 damage and knockback (details unverified).

FAQ

Quick answers to the most common questions about this fight.

How do you beat Rat King in Mewgenics? ▾

Focus on the main loss pattern first: Letting adds accumulate: spawns snowball tempo and block escape lanes. / Standing adjacent carelessly: Toss converts adjacency into collision damage.. Then follow the opener plan: Remove the first wave of adds immediately; don’t let the board fill..

What does Rat King do in Mewgenics? ▾

Add-spawning trample boss with throws; control the board or get swarmed.

Where is Rat King found in Mewgenics? ▾

Rat King appears during a later home-base defense sequence after the Boneyard progression line.

What counters Rat King? ▾

Bring: AOE or efficient cleanup Avoid: Single-target-only damage with no cleanup If notes are partially unverified, assume the worst-case version until confirmed in-game.