Fishmen Invasion Mod

Fishmen Invasion Mod turns fishing anywhere into escalating combat-fishing events, including custom islands and the open ocean. Defeat ordinary fish to draw the attention of the Fishmen, survive increasingly dangerous rounds, and face a named boss every tenth wave. Fallen Fishmen remain physical catches: pick them up, let gulls steal them, cook them from raw to brown and then burned black, eat them, or sell them.

Flashing-lights warning: Invasions and boss fights use lightning flashes. Players with photosensitivity or anyone who prefers a calmer effect should disable Lightning flashes in Fishmen Invasion Options before starting an event.

Quick guide

Feature	How it works
Where events work	Events can start wherever living players are fishing, including modded islands and open water. Fishmen rise from clear water roughly 18–65 m from a living player. If no safe water is nearby, spawning waits and retries.
Trigger an invasion	After loading a world, the host receives a fresh random goal of 5–20 defeated fish. Reaching it starts the next wave.
Force a wave	Pause the game, open Fishmen Invasion Options, and choose Force Start Wave as the host.
Force a boss	The host can choose Force Random Boss Event beneath the wave trigger to immediately start a randomly selected boss encounter.
End an event	During an active invasion, the host can choose End Event / Kill All Living Fishmen to stop it and despawn living enemies and the boss. Defeated bodies remain available.
Test later waves	The host can raise or lower the next wave and starting round, or reset wave progress, from the options panel when no event is active.
Survive rounds	Waves 1–2 have one round. Wave 3 introduces multiple rounds, with later waves reaching up to four rounds. Each round begins with thunder and lightning.
Enemy variants	Normal Fishmen appear first. Brutes and Leapers begin mixing into waves from wave 3 onward.
Random sizes	Ordinary enemies spawn from 0.5x to 1.5x size. Large Fishmen move more slowly; small Fishmen gain up to 20% speed. Bosses retain their larger boss scale.
Living enemy limit	Normal rounds keep at most 10 living Fishmen active. Enemies enter every 0.5 seconds and queued replacements spawn as active enemies are defeated.
Boss waves	Every tenth wave spawns one named boss at 2.5x–3x scale and keeps up to ten Fishmen minions active until the boss falls. Even the smallest boss is larger than the largest possible minion.
Difficulty	Regular Fishmen start at 105 HP (3x the prior base); bosses start at 10,000 HP before host health settings. Health, damage, damage reduction, and pursuit aggression increase gradually with wave number.
Boss defeat	Defeated bosses use the game's own bloody BossDeath explosion, death and explosion audio, screen shake, and blood decals before the body disappears.
Boss numbering	Boss encounters are numbered persistently per world. The left side of the boss bar displays BOSS 1, BOSS 2, and later event numbers.
Revenge bosses	A defeated boss has a small chance to return once as Revenge of [name], with a bright red health bar and stronger stats.
Descendants	Previously encountered bosses can rarely inspire a comedic SPAWN OF encounter.
Event display	The top meter shows wave, round, completed waves, and active enemies. Boss fights add a second boss name and health bar.
Accurate contact damage	Every model uses a compound hitbox fitted across its visible body and limbs. Contact damage reaches the model edges without extending beyond its maximum dimensions.
Cooking and selling	Defeated enemies work as creature items and retain their individual model while held, cooked, sold, eaten, or targeted by gulls.

Enemy roster

Enemy	Behavior
Fishman	Uses the Tuna boss attack base, jumping, spinning, and throwing itself toward players.
Fishman Brute	More health and damage, with a slower but persistent rolling chase.
Fishman Leaper	Less health, the highest and most frequent jumps, faster pursuit, and strong mid-air steering.
Deepjaw	Heavy boss variant using the vanilla Goblin Shark attack base.
Barnacle Colossus	Armored-looking boss variant using the vanilla Goblin Shark attack base.
Tidecaller	Fast boss variant using the vanilla Goblin Shark attack base.
Puffer Titan	Large boss variant using the vanilla Goblin Shark attack base with heavier movement.

All standard Fishmen models are 15% larger than the original version before their 0.5x–1.5x random size multiplier is applied. A server-side recovery check watches movement, progress toward the nearest player, terrain overlap, and under-map position. A blocked Fishman is moved to clear water near a living player and immediately relaunched toward the fight.

Boss encounters

Every tenth wave chooses one of the four supplied boss models and a funny pirate-style name. Bosses use a separate 2.5x–3x size range, which keeps the shortest boss model larger than the tallest 1.5x minion. Boss music replaces the normal event track, a separate health bar appears, and lightning can strike throughout the fight with at least four seconds between strikes. Up to ten minions remain active while the boss lives. On defeat, the boss model disappears inside the same bloody BossDeath explosion, sound, screen shake, and decal sequence used by vanilla bosses.

Boss history is saved per world. A previously defeated boss can return once in a stronger Revenge of encounter. Once that revenge is defeated, that boss cannot return again. Rare SPAWN OF names can appear only after their parent has already been encountered.

If every player dies during an invasion, the event ends and all bodies created by that event are removed. Ordinary defeated bodies also have a three-minute unattended cleanup window to prevent long sessions with many abandoned physics objects from slowing down.

Fishmen Invasion Options

Press Esc, then select the teal Fishmen Invasion Options button with yellow text near the top center. The panel is modal, so clicks do not activate the vanilla pause menu behind it, and you can drag it using its title bar.

• Enable Fishmen invasions — host control for the shared event system.
• Lightning flashes — host-controlled visual setting synchronized to the lobby.
• Event music — host-controlled music setting synchronized to the lobby.
• Event music volume — host-controlled 0–100% slider that changes the playing music immediately and saves for future sessions. The default is 70%, which is 30% quieter than earlier releases.
• Fishmen amount per round — 0.50x to 3.00x host multiplier.
• Fishmen health — 0.50x to 3.00x host multiplier.
• Fishmen attack — 0.25x to 2.00x host multiplier. Base attack grows gradually with wave number.
• Invasion frequency — 0.50x to 3.00x. Higher values reduce the fish-defeat goal.
• Force Start Wave — immediately starts the next scaled event wherever you are fishing.
• Force Random Boss Event — immediately starts the next numbered boss encounter with a random boss model and eligible boss-name behavior.
• Invasion Progress — shows the current or next wave and round, fish remaining before the next wave, and waves and rounds until the next boss.
• Wave − / + and Round − / + — host-only testing controls for the next encounter; available between events and saved per world.
• Reset Waves and Rounds to Zero — clears completed-wave progress and resets the fish goal. Boss history remains intact.
• End Event / Kill All Living Fishmen — lights up only while an event is active. The host can stop the event and remove all living Fishmen and bosses immediately.

Only the host can change event enablement, balance, lightning, music, or event music volume. Those values are synchronized to every player. Every player should install the same mod version so all seven network prefabs and event state messages match.

Installation

Install and enable the package with Thunderstore Mod Manager or r2modman, then launch How to Fish through the manager. This version uses item IDs 238–244 and FishNet prefab collections 42426–42432.