The undead are coming — wave after relentless wave — and you're the last one standing. Undead Invasion is a pixel-style side-scrolling zombie survival shooter that blends intense combat with tower-defense strategy, and you can play it free in your browser right now on PLRun.
Undead Invasion is a roguelike zombie survival game built as an HTML5 browser game. Released in 2024, it places you in the role of a lone post-apocalyptic survivor defending a ruined orphanage against escalating hordes of the undead. The game combines side-scrolling shooting with defensive planning — you fight zombies with firearms, melee weapons, and grenades while placing barricades and traps between waves to slow the next assault.
The core loop is brutal and addictive: survive a day, earn coins, buy upgrades, and prepare for an even harder tomorrow. There are no checkpoints. Death means starting over completely, which gives every decision real weight. With its pixel art style, diverse zombie types — from fast crawlers to armored brutes — and a deep weapon and trap system, this free online game delivers high-stakes survival action that rewards strategy as much as reflexes. The game also features two modes: a main survival campaign and a Playground mode for experimentation.
Undead Invasion uses a keyboard-and-mouse control scheme on desktop:
On mobile, the game uses virtual on-screen controls including a joystick for movement, weapon switch icons, and tap-to-shoot mechanics.
Undead Invasion structures gameplay around a day-night cycle. Each new day brings a wave of zombies that is larger, faster, and more dangerous than the last. Your objectives each day are straightforward:
This loop continues until your character is finally overwhelmed and killed. Since there are no checkpoints, every run starts fresh from Day 1.
You have access to multiple weapon types including firearms and melee weapons. Ranged weapons let you pick off zombies from a safe distance, while melee attacks and kicks serve as your close-quarters emergency tools when undead breach your perimeter. Grenades are your crowd-control option — save them for moments when zombies cluster together in tight groups for maximum efficiency.
Maintaining distance is critical. Zombies deal damage when they get close, so constant repositioning while shooting is essential. When enemies do close the gap, a well-timed kick pushes them back and buys you space to resume firing.
Between waves, you can place barricades, drop traps, and set up other defensive structures to slow incoming zombies. Proper placement is crucial — well-positioned barricades funnel zombies into kill zones where your weapons are most effective, while traps deal passive damage that softens enemies before they reach you. Investing coins in defense items is just as important as upgrading weapons, especially in later days when zombie density becomes overwhelming.
Coins earned from kills and survived days are spent in a between-wave shop. You can purchase:
Smart upgrade prioritization is the difference between surviving Day 10 and dying on Day 5. Every coin matters because death erases all progress.
Undead Invasion features two distinct modes:
Zombies deal damage when they reach melee range. Your primary survival tactic is to keep shooting while backpedaling — never let them close the gap. If you find yourself standing still while firing, you're already making a mistake. Constant movement buys time for your weapons to thin the horde before they arrive.
Grenades are your most powerful crowd-control tool, but wasting them on one or two zombies is a costly mistake. Wait until five or more undead are grouped tightly together, then throw. A well-placed grenade can clear an entire cluster that would have taken ten seconds of shooting, saving both health and ammunition.
Many players pour all their coins into weapons and neglect barricades and traps. This works on Days 1-3 but falls apart fast. By Day 5, zombie density is too high for shooting alone. Place barricades to create chokepoints and lay traps in front of them. This layered defense slows zombies significantly and lets your weapons do their job from a safe distance.
Health items are a temporary fix — they restore damage you've already taken. Weapon upgrades prevent that damage by killing zombies faster before they reach you. In the early days, invest heavily in firearm damage. Switch to balancing health and defense spending once enemy waves become too dense to clear before they arrive.
When a zombie reaches melee range, your first instinct might be to keep shooting. Instead, kick first. The kick pushes enemies back, creating space for you to resume firing from a safer distance. This split-second breathing room prevents the chain reaction where one zombie reaching you leads to three more piling on.
Before committing coins to a specific trap layout or weapon combination in the main campaign, test it in Playground Mode first. Since Playground removes the permadeath penalty, you can freely experiment with barricade positioning, trap placement, and weapon effectiveness. The knowledge you gain transfers directly to better decision-making in the real survival runs.
With no checkpoints and full progress reset on death, reckless play is punished severely. Don't rush into zombie clusters for a few extra coins. Don't skip defense placement to save time. Don't hold off on upgrades hoping to save for something expensive later. Spend wisely, play conservatively, and remember that surviving one more day is always worth more than a risky gamble.
Please share by clicking this button!
Visit our site and see all other available articles!