Games like Operation: Outbreak Idle

Hardcore open-world survival where preparation is everything. Scavenge, craft, fortify during the day. When night falls, the infected hunt in numbers. Play solo or with friends in a brutal post-apocalyptic sandbox where survival is earned through smart decisions. How many Nights will you survive?

Build your base on a moving Machine, travel through biomes with different resources, and prepare for the night when a zombie threat is much higher than during the day. Would you go solo or explore this new world with your best friends?

Build your towers and let them do the killing! Connect 12 unique towers through the Reactor to discover 144 devastating synergies. Kill endless zombie hordes, mutate them for bigger rewards, and push your build to the limit in a chaotic bullet hell.

This is a multiplayer cooperative open world construction survival sandbox game, where you and your friends must find supplies and build shelters in this world. You have to keep an eye on your character's needs state at all times, a bad state is likely to lead to death.

Defend. Upgrade. Dominate. A relaxing incremental base-defense game, packed with powerful skills and a deep skill tree.

The Front is a survival open-world crafting sandbox game. You are a resistance fighter sent back in time to stop the rise of a tyrannical empire. Collect resources, craft tech, build shelters, and fight monsters to accomplish your mission.

The Horde is coming, but you're ready to fight it! Assemble your squad, choose their upgrades, and build powerful synergies against thousands of undead. Survive. Then evolve. Then break every limit in this deceptively simple but addictive bullet heaven game.

Build twisting mazes with tetromino blocks and deploy unique towers in this strategic roguelite tower defense adventure!

HumanitZ is an isometric, open-world sandbox survival game set in a world ended by a zombie outbreak. Survive alone or with friends by scavenging, crafting, building, and fighting to last as long as ‘humanly’ possible. You can’t change the past, but you can fight for the future of humanity.

No More Room in Hell 2 is an intense 8 player zombie shooter. Overcome the endless undead. Avoid infection. Survive hell together.

A short incremental siege game centered around growing and strengthening an army to defend your kingdom. Seize the crown from an endless wave of enemies for your best chance at survival!

Mine by day, defend by night. Master 25+ spells, sell rare ores for gear upgrades, and grow stronger each run in this procedurally generated roguelite tower defense. Enjoy full controller and Steam Deck support.

Fight hordes and defend your Stronghold in a bullet heaven survivor-like with co-op and tower defense. Gain power-ups every level, collect random artifacts from chests and grow stronger to survive, defeat the boss and claim a top spot on the Sineus Arena leaderboards!

Become a crew member of an Interdimensional Express Train! Discover a new world full of mysterious creatures, enemies and places. Upgrade and customize your train, gather new materials and build better weapons. Play solo or online сo-op with up to 4 people.

Into the Radius 2 is an immersive VR survival shooter, set in a realm of surreal landscapes and deadly entities known as Pechorsk Anomaly. Arm yourself with realistic weapons and venture deeper into the mysteries within. Featuring co‑op for up to four players.

Open world zombie survival Coop game with base building, looting, crafting, vehicles, and exploration.

Build and manage your own castle settlement in a land reclaimed by wilderness. With detailed management, survival strategy, and a moddable sandbox world, Going Medieval challenges you to build the mightiest colony this side of the apocalypse.

Trapped in the twisted game room of a mysterious entity, Dealer's Dice is a high-stakes roguelike dice-defense game. Collect powerful dice, manage your betting table, and gamble against relentless waves of invaders. Push your luck, test your greed, and survive.

A corner screen incremental brick-breaker where bouncing cores destroy endless swarms. Let it run in the corner of your screen while you work or jump into fullscreen and take control yourself. Unlock new Cores, expand your skill tree, survive endless waves.

You have only 5 minutes to stylishly explode your way through the hordes of corrupted entities in a retro FPS, roguelike liminal-nightmare... and Timmee is here to help!

You are a disease. Infect the human body as a lone pathogen in this cellular roguelike shooter. Collect organelles to evolve your parasite in a microscopic arms race against your host's immune system. Conquer a beautiful, procedurally generated world of tiny proportions.

RoundZ is a solo-developed round-based survival zombie game, with each round becoming progressively harder as the zombies get more health and in bigger waves. 

In Call of Duty®: Black Ops 7, Treyarch and Raven Software are bringing players the biggest Black Ops ever across an innovative Co-Op Campaign, an electrifying Multiplayer experience, and the legendary Round-Based Zombies mode.

Fortress Fury is a survivor multiplayer tower defense roguelite. Endless hordes of enemies want to crush your tower! Buy weapons and upgrades to craft an array of overpowering builds. Will you be able to survive all waves and be the last tower?

Welcome to UMAN - Become a cog in the machine - Work, sleep and don't ask questions - Collect your trash, hit your quota, consume, upgrade and meet your coworkers. But whatever you do... don't look into the eyes.

Isometric action shooter with light RPG elements. Brutally kill tons of alien monsters, find over a dozen powerful weapons, skill up your hero & stop the blood thirsty invaders in a classic handcrafted campaign. Never ending waves await you in horde-mode!

The Perfect Tower II is a mix between an incremental and a tower defense game. Build a town, manage resources and explore a variety of mini-games and tons of upgrades. Fully automate your game and watch numbers going up!

Jump into this free‑to‑play looter‑shooter RPG featuring tactical combat, deep progression, and an exclusive canon storyline, playable solo or with friends.

On RuneScape's forgotten continent of Ashenfall, dragons have awoken. Gather, build, skill and craft in this co-operative survival adventure. Only by mastering survival and uncovering ancient secrets can you hope to face the ferocious Dragon Queen.

Drive, ram, and blast through endless zombie hordes in a top-down vehicular action game, then upgrade your weapons, unlock brutal war machines, and carry your growing arsenal into the next run.

A first-person shooter meets quarantine inspection in post-apocalyptic Chicago. You’ve got 30 days until the army arrives. Hold out, fix your car, and fight your way through Chicago to the main checkpoint to save your little brother.

From a small village of a dozen people to a small kingdom of thousands of people. Arrange for residents to work, gathering, fishing and hunting, farming and mining, processing and manufacturing. Trade, accumulate supplies, increase your strength, and fight evil forces and monsters.

Guard your campfire through the night and feed your rivals' rifts with monsters. A multiplayer tower-defense survival hybrid where deck building, base building, and dueling economies decide who survives and who freezes.

Winter Survival is a story-driven survival game where trauma turns reality into a reflection of your breaking mind. Battle cold, hunger, hallucinations, and adapt to the wilderness as it adapts to you.

Whack-A-Monster. An incremental game about Whacking, Smashing, Splashing & BONKING monsters. Upgrade through the skill tree and unlock new weapons to vanquish all evil from this world.

A dynamic platformer with lots of blood and chaotic shooting. Unleash your desire for violence by killing crowds of enemies, hastily injecting yourself with another dose of experimental drug.

Embark on your creative journey of vehicle design, as you create and operate vehicles to survive this dangerous open world. Anymaker is a detailed and technical vehicle builder and survival game. Design your chassis, build your engine, connect components, and travel into the unknown.

Critter Chaos TD is a fast, frantic and chaotic Tower Defence game in which you must rid the world of the evil Critters. Build stations and guns to fortify your defences and prevent the various types of Critters from reaching your base.

An incremental auto battler dungeon crawler where you build a synergized hero party to slay enemies and loot items. Unlock weapons with unique attack styles. Gear up your hero team and explore new dungeon rooms filled with enemies and legendary drops.

Golden-age RTS classic. Fast-paced action & strategic decision-making, battling evil arch-enemies, zombies, and retro-futuristic technologies. All to a '90s electro-metal soundtrack and FMV live-action cut scenes.

You are the Kingdom’s Commander. Choose new contracts strategically. Use towers but save your gold. Use 12 powerful God/saint spells. Finish Contracts quickly. Stack gold and reputation rapidly. Choose and upgrade 36 perks blessed by 12 Gods/saints. Become the Legend of the Kingdoms.

DEADSWITCH COMBAT is a fast-paced 2D multiplayer shooter. Experience action-packed combat with hundreds of weapons, vehicle combat, and plenty of team-based game modes.

Humans are long gone. In a world struck by droughts and toxic waste, will your lumberpunk beavers do any better? A sandbox city-building game featuring ingenious animals, vertical architecture, water physics, and terraforming. Contains high amounts of wood.

Fight, farm, build and work alongside mysterious creatures called "Pals" in this completely new multiplayer, open world survival and crafting game!

Can you Survive the Swarm? Unlock mighty abilities and upgrades, find and collect Tems to evolve and become stronger, discover overpowered strategies, and battle massive bosses in this survivor-like bullet heaven! Play solo or online co-op with up to 3 players, building the wildest synergies.

The ultimate all-out warfare experience. In a war of tanks, fighter jets, and massive combat arsenals, your squad is the deadliest weapon.

Bullet Heaven x Endless Loot! Create Your Own Build in this Roguelite Action RPG.

Perform a dark ritual with your own hands under relentless pressure. Draw runes in real time, defend the ritual from enemies trying to stop it, and upgrade your skills to unleash devastating magic. Summon ancient eldritch gods in this dark fantasy game driven by skill, strategy and constant tension.

2D Strategy game.

Don the Ancient Mask. Wield the power of gods. Possess any of your tribespeople, recruit followers, and build a thriving automated civilization. Survive, expand, and forge your own legacy across a vast ancient open world — together with friends.

Incremental clicker strategy, where you expand, construct, research, fight, collect heroes and make choices between good and evil. Ascend through difficulty tiers by playing through challenge campaign going back and forth through history. Mammoths included.

Build, quest, and conquer across an infinite procedurally generated world. Play alone or with friends as you establish a settlement and explore deep dungeons, fight monsters and bosses, mine rare ores, craft magical equipment, recruit specialists for your colony, and more!

MycoRelic is a cooperative third person action-RPG set on islands inhabited by tribal mushroom robots. Loot derelict foundries to upgrade your robotic body. Explore ancient temples to infuse your fungus with forgotten elemental powers.

A highly realistic VR survival roguelike adventure set on a ruthless 17th-century tropical island. Shipwrecked and alone, you must survive without guidance as you face wild beasts, nature’s fury, and a mysterious local tribe. Every decision is yours. Your survival is in your own hands!

Purge the billionaires' robot army with your Merc squad! Fast-paced twin-stick action, frantic horde survival, tactical squad-building & tons of loot! Exploit game-breaking synergies to beat the M.E.G.A. Corp. bosses in ever-changing operations. Lock, load, and loot, Commander!

"Cultivation Tower" 2.0 "Cultivation Road", 2D side-scrolling idle cultivation game. Lead the protagonist and 12 fellow cultivators on an automatic journey along the immortal path, battling and collecting treasures, managing your sect, constantly reaching new heights in twenty different scenes.

Repterra is a base-building survival RTS set in a world overrun by dinosaurs. Manage your colony while battling massive dino hordes. Breed and ride your own dinos, unlock permanent upgrades, and fight to reclaim the world for humanity.

Survivors-like with ONLINE CO-OP for 1-4 players. Team up with your wizard friends to slay hordes of dark creatures. Complete team-based objectives, unlock new upgrades and create overpowered spell synergies. Friend nor foe is safe in this friendly fire bullet hell!

Recruit cards, assign them to shelters, and stop incoming waves in a strategic tower defense game. Combine three cards to strengthen your forces, manage limited resources, and adapt to each scenario.

Enter the creative paradise of Scrap Mechanic! Build fantastic machines, go on adventures with your friends and defend against waves of evil Farmbots in this imaginative multiplayer survival sandbox. With Scrap Mechanic’s powerful creation tools you can engineer your own adventures!

Darkwater is a cooperative extraction horror game for 1-4 players. Command a submarine trapped under the ice of an alien planet. Battle enemy vessels and deep sea abominations as you hunt for resources. Do what it takes to survive.

Start with one bullet. End with hundreds. Crystalyn is a fast-paced top-down bullet-hell looter shooter about pushing your build to its absolute limits. Fight monsters, defeat bosses, and turn their loot into unstoppable firepower.

Will your castle survive the relentless onslaught, or collapse under pressure? Build, manage resources, and outsmart your foes in a world where everything can be destroyed. Use strategy and creativity to turn the chaos into your greatest advantage!

Rebuild your kingdom and explore a vibrant fantasy world in this roguelite city builder. Defeat hordes of monsters with a unique team of defenders as you harvest, build, mine, cook, brew, and grow. But if your defenses should fail, be prepared to watch it all burn!

Claws of Power is a cute, real-time card battle game. With a variety of unique and adorable cat cards, each one could be your key to victory. Strategize by building different decks and using items to overcome challenges and claim the throne as the ultimate cat leader.

By day, you run a DVD store in 2012 New York. By night, you’re a ruthless assassin. BLACKWOOD is a cinematic third-person shooter with grounded melee combat, brutal takedowns, responsive gunplay, and a double life to manage.

Exorcise hordes of demons using gun-wielding nuns and angels in this survivors-like bullet heaven! Collect and keep angels with unique weapons, stats, and abilities to create god-like builds as you fend off waves of enemies! Do you have enough faith to survive?

Play as a kind-hearted god in a tiny world. Grow thriving forests, inspire mortals to stand strong, and unleash nature's fury to shield them from evil. One small miracle at a time.

KILL IT WITH FIRE! 2 is the ultimate co-op spider-hunting experience! Either solo or as a team of Exterminators, unleash an arsenal of crazy weapons, wreak havoc, and complete dozens of challenges across seven dimensions under spider siege.

Sail, scavenge, and rescue survivors in a vibrant floating city-builder. Captain your drifters across the endless garbage sea to uncover soaked ruins, rusting factories, and stories from the old world.

MASTER YOUR MOVEMENT. VANQUISH THE VERMIN. Experience all the exhilarating high-intensity action you know and love from arena shooters up close and personal in VR. Zero in your aim, hone your movement, outwit the vermin, and soon you’ll be flying through levels leaving a wake of destruction.

A fast paced silly cutegore FPS! Earth has been taken over by demons. A catgirl codenamed MeowMeow fights back! MEOW, GUN, CLAW and BLOW UP hordes of evil demons, zombies, and other monsters in colorful environments with tons of weapons! The game runs on the FTEQW engine.