Games like Zero Stress King: Idle Defense
Zero Stress King: Idle Defense. These games share the most with it, and each one says why.

Abyss Manager Idle
Also tower defense, short, idle
Assign characters to jobs, gather resources and dig deeper floors in an idle tower defense. About two hours to finish completely.
95% steamhas ending
castle idlerUpdated
Also tower defense, short
A tower defense incremental without waves, where you place and upgrade towers against slimes and unlock a prestige skill tree across harder levels.
79% steam3.6★ galaxy
Sir, We Have an Orc Problem
Also tower defense, short
A short tower defense against orc armies in the tens of thousands, where every run, won or lost, feeds a big tree of turret upgrades.
86% steam
Spellbound & Shelved
Also short, idle
Hire gnomes to reshelve thousands of spilled spellbooks in a wizard library. Flip the sign to trade customer income against the mess they make, until the last book is put away.
87% steamhas ending75% idle
OutholdUpdated
Also tower defense, short
A short tower defense run-based game where you spend collected resources in a large refundable skill tree between attempts.
4.4★ galaxy
An Ordinary Vanilla JS Idle Game
Also short, idle
A short experimental idle game about piling up points and lasting as long as you can.
3.4★ galaxy
The Tower - Idle Tower DefenseUpdated
Also tower defense, idle
Defend a single tower against waves, buy permanent upgrades and research while idle or active.
50% idle
Zombie Idle DefenseUpdated
Also idle, tower defense
Equip survivors with weapons and hold a defensive line against waves of zombies and bosses across post-apocalyptic levels.

Dice vs Monsters: Roguelike TDUpdated
Also tower defense, idle
A roguelike tower defense where each hero is a die, with dice rolls used to upgrade abilities against monster waves.

Slime Castle: Idle TD RTS GameUpdated
Also idle, tower defense
Play as a slime defending a forest castle from human invaders, gathering gear and skills and returning stronger after each defeat.

Idle Archer Tower Defense RPGUpdated
Also idle, tower defense
Defend a tower as a lone archer against monster waves, collecting skill cards and spending gold on permanent upgrades after each loss.

Idle Kingdom DefenseDormant
Also idle, tower defense
Command heroes and archer corps in large castle-defense battles, with rewards stacking up while the game is closed.
75% idle
Medieval: Defense & ConquestDormant
Also tower defense, idle
Build a crusader settlement's farms and trade, then spend the income on an army and walls to hold off waves of attackers.

Rogue with the Dead: Idle RPGUpdated
Also idle, tower defense
March an army 300 miles to slay the Demon Lord; troops fight automatically, and each death resets your run but makes you stronger.
has ending75% idle
Mega Tower - Casual TD GameUpdated
Also tower defense, idle
Merge and modify towers in a sci-fi tower defense that fights on its own but lets you aim manually.
50% idle
Dead Spreading:Idle GameDormant
Also idle, tower defense
Recruit soldiers and upgrade a base to hold off zombie waves while balancing defense and supply gathering.

Eternal Cannon Idle ShootingDormant
Also idle, tower defense
Defend a city with an upgradable cannon and walls, mixing tapping and upgrades where each level brings a new skill.
50% idle
Geometry Tower: Idle DefenseUpdated
Also tower defense, idle
Defend a single tower against endless waves, picking roguelike upgrades each run and researching permanent boosts.

Kitty Keep™Updated
Also tower defense, idle
Cat heroes defend a beach castle from sea creatures in an idle tower defense that runs on auto-battle.

Tiny Warriors Rush - Idle TDUpdated
Also tower defense, idle
Pick warriors and random upgrade cards in tower-versus-tower battles, then spend winnings to level your army.

Idle Defense: Dark ForestDormant
Also tower defense, idle
Play a banished trainee wizard who deploys turrets to hold off monsters released from a shattered seal.

Tower Defense: Lazy ApocalypseUpdated
Also tower defense, idle
Play a monster-slaying streamer holding off zombie waves, upgrading weapons while your hero keeps fighting when you are away.
75% idle
Magic ArcheryUpdated
Also short
Train an elf commoner into a master archer by shooting targets, taking quests for gold and buying magic upgrades in a brief, hands-on climb with a set ending.
98% steamhas ending25% idle
SpaceplanComplete
Also short
A stranded ship, a potato, and a soundtrack that makes the finale land. A short, focused story idler.
91% steam1–3h ending30% idle