Nano Siege
Play a free idle tower defence game online. Hold endless waves, upgrade towers forever, and keep earning while the tab is closed.
About Nano Siege
Nano Siege is a tower defence game with no last level. Orbs walk a fixed track towards your core, you line the track with towers that shoot them, and the waves keep coming - each one heavier than the last, every tenth one a boss, forever. Nothing starts on its own: between waves the board sits in a build phase with no clock on it, showing you exactly what is about to walk in and how it behaves, and it stays there until you press Launch.
From wave twelve those waves start arriving with modifiers - armour that shrugs off small hits, shields that ignore splash, speed that outruns your guns, regeneration that undoes anything you cannot finish - and each one is beaten by a different tower, so the build phase is where the game is actually played. If you would rather it ran itself, auto-launch starts every wave for you, including while the tab is closed.
Popping an orb does not delete it so much as peel it: everything above the smallest tier breaks into children of the tier below, so a single Titan is really a stack of Novas hiding Voids hiding Prisms, and a board built entirely around one big damage number will drown in the debris of its own kills. Spending is endless in both directions. Flux buys towers and then levels on those towers, and the levels never stop - but wave health compounds faster than any single upgrade line does, so every base eventually meets a wave it simply cannot clear. That wall is the game.
Overclocking scraps the entire board in exchange for sigils, which are permanent, and the next climb goes further than the last one. On top of that sit perks bought with site credits and nano cores: permanent, account-wide upgrades that survive every reset, from a flat damage boost to an Auto-Deploy Core that does the shopping while you sleep. In a lobby everybody plays the base they already own and the room becomes a ladder, so a group can race waves without anyone having to start over.
How to Play Nano Siege
Nano Siege Rules
- There is no final wave. Waves run one after another, endlessly, and each is worth more flux than the last.
- Nothing starts until you launch it. Between waves the board sits in a build phase with no timer, showing exactly what is coming next.
- Orbs walk a fixed track towards your core. Towers stand on twelve pads beside it and fire on their own once a wave is launched.
- Every orb tier above the smallest breaks into children when it pops, so the wave you see is smaller than the wave you have to kill.
- Flux is the in-game currency. It comes from clearing waves, from popping shells, and from Flux Harvesters that print it every second.
- There are six towers: Pulse Emitter for constant damage, Scatter Coil for crowds, Frost Node to slow, Ion Lance to pierce a column, Railgun for single heavy targets, and Flux Harvester for income.
- Every tower can be aimed at the first, last, strongest or closest orb in its range. Re-aiming is free and works mid-wave.
- From wave 12 some waves carry a modifier you can read before launching: Armored shrugs off small hits, Shielded ignores splash, Swift outruns your guns, Regenerating heals itself, and a Swarm arrives in twice the numbers.
- Once per wave you can trigger Overdrive, which more than doubles every tower's fire rate for six seconds.
- Towers upgrade without a level cap. Cost climbs faster than damage does, which is what eventually stops any board.
- Letting too much of a wave through breaks the line. That wave is simply re-armed for you to try again with everything you have bought since - you never lose the base.
- Every tenth wave is a boss: far heavier, and worth triple flux.
- Every twentieth wave is the last one on its map. Clearing it moves the whole siege to a different map with a different track and a different set of pads.
- Moving takes your towers off the board and refunds every one in full, so you rebuild on the new map with all the flux you had sunk into the old one.
- Each map you clear is a permanent 20% damage and 20% flux bonus for the rest of the run, which is what makes the second half of a run faster than the first.
- At wave 25 you can Overclock: the board is scrapped and you bank sigils, each worth a permanent 9% damage and 7% flux.
- Perks are bought with site credits or nano cores. They are permanent, they survive every Overclock, and none of them are required to reach any wave.
- Turn on auto-launch and waves start by themselves - including while the tab is closed, at half rate for up to twelve hours, and longer and faster with the right perks.
- In a lobby everyone plays their own base and the room ranks players by the wave they reached. The host closes the siege to end it.
Tips to Win
- Buy a Flux Harvester early. It is the only tower that pays for the ones after it, and every hour it is not on the board is an hour of income you never get.
- Coverage beats raw damage. A pad that only sees a short stretch of track spends most of the wave with nothing in range, so a cheap tower on a corner often out-damages an expensive one on a straight.
- A Frost Node deals almost nothing and is still one of the strongest buys on the board: an orb held in range longer is an orb every other tower gets extra shots at.
- Watch what a wave breaks into rather than what walks on. When Voids arrive, splash stops being optional.
- Overclock as soon as it is offered. Grinding a few more waves for a slightly bigger payout almost always costs more time than the extra sigils give back.
- Spread your towers before you deepen them. Twelve pads at level five clear more than four pads at level fifteen, because the wave has to survive the whole track rather than one corner of it.
- Read the modifier before you launch. An Armored wave against a board of Pulse Emitters is close to unwinnable, and the fix - one Railgun, or simply re-aiming what you already own - costs seconds in a build phase that has no timer.
- Targeting is free, so treat it as a per-wave setting rather than something you configure once. Last is for softening a column early, Strongest for bosses, First for stopping leaks.
- Save Overdrive for the moment the column bunches up, not the moment the wave starts. Six seconds of doubled fire rate into a crowd is worth far more than six seconds into the first two orbs.
Best for
Nano Siege is for people who like tower defence but not losing an hour of progress to one bad round, and for people who like idle games but want something to actually watch. It suits players who enjoy tuning a board, arguing about whether income or damage comes first, and the specific pleasure of coming back to a base that got further without them. It works completely solo, and in a lobby it becomes a race rather than a co-op, so nobody is waiting on anybody else to take a turn. There is no reading speed, drawing, trivia or typing involved, which makes it an easy fit for a mixed room.
Nano Siege FAQ
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