Operation Octo

Play as an Octopus scientist fighting off sunken skeletons in this frantic aquatic Tower Defense! Discover sea life turrets from unique biomes: Pistol Shrimp! Navy Seal! Death Ray! Deploy turrets whilst dodging enemy bullets as you venture the seven seas!

Action Strategy Adventure

Developer

Klub Kofta Studio

Released

10 Sep 2025

1 year ago

PC Mac

£5.89

Buy on Steam

Overview

Summary

Description

About This Game

Join Our Discord Server!

About the Game

Dr. Odin, an octopus scientist, has teamed up with his Dolphin colleague to put a stop to underwater skeletons’ reign of terror!

In this action Tower Defense game, you fend off hordes of skeletons by strategically placing sea creature turrets. Beware that as your line of defense falls, this quickly turns into a game of survival where you dodge around for dear life!

The game currently has 7-9 hours of playtime across 3 unique biomes, with more biomes to be added via free updates!

Features

Unlock Turrets: Your arsenal is filled with mechanized sea lives! Those cool inventions (such as Pistol Shrimp, Navy Seal, and Death Ray) will handle the fight. You’ll discover new turret types one after another - Figure out how best to utilize each of ‘em!
Skeleton Enemies: Did you know that most humans who ever lived are dead? Tons of skeletons end up in the ocean, and are terrorizing local ecosystems. Fight sword-swinging pirates, poison-wielding chemists, and even skeletal dragons… Those skeletons are sure to shake up your playstyle at every turn!
Unique Biomes: As you adventure the seven seas, you’ll add more creatures into your turret collection, and face new and exciting dangers. Adapting to changing environments is key to survival: Don’t misstep into a toxic brine pool, or forget your light in the darkness of the deep sea.
Turret Upgrades: Skeletons will sometimes drop a variety of Elixirs. Use them to boost turrets into different forms! Will you turn a turret into a frosty ice machine, a powerful mutant, or a shadowy stealth weapon?
Boss Fights: Special levels featuring larger-than-life boss enemies with formidable abilities!
Awesome Upbeat Soundtrack: Seriously, the composers are amazing
Mostly created by one person, while doing college

“The ocean awaits us to reclaim - Let the Operation Octo commence!”
- a message from Dr. Finn the Dolphin (who really needs your help because he’s too lazy to do the work himself)

Technical

System Requirements

Minimum

OS: Windows 7 (SP1) or higher
CPU: SSE2 instruction set support
RAM: 8 GB RAM
GPU: DirectX 11–compatible GPU (Dedicated GPU required)
Disk: 2 GB available space

Availability

Platform Release Dates

Platform	Release Date	Region	Tags
PC	--	--
Mac	--	--

Steam

Features

Family SharingFull controller supportSingle-playerSteam AchievementsSteam CloudSteam Leaderboards

Input

Controller Support

full controller support

Pricing

Price Information

£5.89GBP

Store

Store Links

View on Steam

Community

User Curated Lists

... no lists at all!

So what you may do right now is:

- Check the Most Popular Lists
- Be the first and Create Your Own List starting with this game

Steam

Achievements

The Odin Hypothesis

Complete Level 1-1 “Initial Test”

Bumpy Ride

Complete Level 1-5 “Bumper Maze”

Delivery Received

Complete Level 1-10 “Free Shipment”

Shellfish Husbandry

Complete Level 2-5 “Clam Farm”

Seal the Deal

Complete Level 2-10 “Sergeant's Plateau”

Bone Picker

Complete Level 3-5 “Graveyard Shift”

10,001 Ways that Won’t Work

Complete Level 3-10 “Leviathan Trench”

Flag Down

Defeat Crâne Exalté for the first time

Breach Repaired

Defeat Dr. Kraxen for the first time

Dallons Adrift

Defeat Captain Dallons for the first time

Feeding Frenzy

Complete 20 Sandy Shallows Treat Bucket quests

Acid Reflux

Complete 20 Toxic Wastelands Treat Bucket quests

Late-Night Snack

Complete 20 Twilight Zone Treat Bucket quests

Clam Abandonment

Have the same Clam knocked out 3 times in a single level

You Had One Job!

Have a Bumperfish knocked out by a deflectable projectile

[Hidden Achievement]

Keep playing to unlock

Blob on the Job

Blow up 7 skeletons with a single Blobfish

Chirpy Alarm

Revive 5 knocked-out turrets using Bubble Parrots

[Hidden Achievement]

Keep playing to unlock

Aragonite Profiteer

Collect 130 pearls within 10 seconds

Productive Workout

Acquire 300 pearls from Mussel Beests during a single level (outside of Graveyard)

Permanent Paralysis

Keep a skeleton stunned for 25 seconds using only Zappy Jellies

Fearless Turtles

Finish a level with at least 5 Sniper Turtles on the field, without having scared any of them

Sleepy Bunch

Wake up 5 Hermit Holsters within 5 seconds

Save a Tree

Revive a knocked-out Pearl Tree before it dies permanently

Cycle Deck

Have 3 non-mimic Pearl Trees on the field simultaneously

Responsible Parenting

Have 4 Pearl Trees die in a single level

Photomania

Have 15 Lantern Fish on the field at the same time

Walk the Plank

Permanently lose a turret by having it sink into a lake

Love Me, Love My Dog

Have 7 Watchdogs on the field at the same time

Salty Sea Dog

Evade a Watchdog for 20 seconds while he chases after you

[Hidden Achievement]

Keep playing to unlock

Avid Recycler

Place Hammer Shark 10 times during a single level

Safely Defused

Have Dr. Odin trigger a Bomb Barrel without taking any damage himself

[Hidden Achievement]

Keep playing to unlock

Ping-Pong

Have a projectile deflected between a Bumper Fish and a Racquet Skeleton for 3 rounds

Friendly Freeze

Get slowed down by your own Frosty turret

Quick Reflex or Dumb Luck

Sink a Racquet Skeleton into a pool using Zappy Jelly while it is dashing

Davy Jones’ Smelter

Sink 5 Skeletons into lakes

Break Time

Interrupt a Diver Skeleton’s drill after it has reached max charge

Tea-bone Party

Have a Leaky Dropship drop all three of its crews into lakes

Say No to Vandalism

Destroy a spinning spray can using Zappy Jelly or Blobfish

Ping-Pong For Boomers

Have a Boomerang deflected between a Bumper Fish and a Racquet Skeleton for 3 rounds

Aye Yai Yai, Captain

Prevent Captain Phantom from dealing damage to anything for an entire level

Cheating Death

Wake up or recycle a knocked-out turret as a Reaper Skeleton lifts his scythe to destroy it

Live Deliciously

Fail a level for the first time

Octo Fiasco

Somehow manage to fail Level 1-1 in tutorial mode

[Hidden Achievement]

Keep playing to unlock

[Hidden Achievement]

Keep playing to unlock

Geometry

During Level 1-5 “Bumper Maze”, have cannonballs bounce off of 4 different Bumper Fish within 2 seconds, while Odin stands still and takes no damage

Octopus Regeneration

Survive on exactly 1 HP then fully recover before a level’s end

Shove a Bezoar

Have 4 status inflictions on Dr. Odin at the same time

Sufficient Funds

Fill up your entire Pearl Flask during a regular level

Action Star

Beat a regular level without using combat (blue) turrets

[Hidden Achievement]

Keep playing to unlock

Augustus the Great

Die from poison damage over time

Photophobia

Survive a level in Twilight Zone without getting light from Planktons or Lantern Fish

[Hidden Achievement]

Keep playing to unlock

[Hidden Achievement]

Keep playing to unlock

[Hidden Achievement]

Keep playing to unlock

Lab Anniversary

Play the game on its anniversary of release

Penny Pincher

Pick up 200 successive coins without having left any coin to disappear

Institute Fundraiser

Earn a total of 10,000 coins

Wealth by Glamour

Earn a total of 100 rubies

Benefactor of a Dolphin

Spend over 5000 coins at Dr. Finn’s shop

World Peace

Fill up all gravestones inside any one Graveyard Region

Idle Farm

Reach 10 cycles inside a Graveyard Simulation

Appetizer

Feed a total of 10 fish to Dr. Finn

The Beautiful Glow

Pick up a Ruby

Avid Tinker

Discover 5 upgraded turret forms

Untouchable

Complete any level without taking any damage

Bountiful Harvest

Complete Level 2-5 “Clam Farm” in under 4 minutes

Archeologist

Complete Level 3-5 “Graveyard Shift” without getting stunned or taking any damage

A Dime a Dozen

Place down 80 turrets during a single level

Caffeine

Have a sleeping Hermit waken up by a Potion vapor

Dolphlock’s Irregulars

Have 3 Spiky Urchins on the field at the same time (outside of Graveyard or Custom Levels)

Neverending Distraction

Keep a skeleton taunted by the same Red Herring for 10 seconds, without stunning the skeleton

Doppelgänger

Have 2 pink imitated turrets (from Imitation Crabs) on the field at the same time (outside of Graveyard or Custom Levels; Everywhere Eel doesn't count)