Thornwall: one canyon, four towers, sixty waves you cannot get lucky on

01  What Thornwall is

Thornwall is a tower-defense game that runs in a browser tab. You are defending a fortress at the far end of a winding canyon. Void-corrupted creatures walk the canyon path toward your wall, and you build towers on the rock beside the path to stop them before they arrive. Four tower types, three upgrade tiers each, sixty waves, one map. It loads from a URL and plays — there is nothing to install, no account to create and nothing to pay.

The game moves in two beats, and the split is the whole design. In the placement phase you spend gold: pick a tower type, click one of the eighteen build nodes along the path, and the tower goes up. Click a tower again to upgrade it or sell it back for 60% of everything you put into it. When you are ready you start the wave. Then the game takes over — the watch phase — and your towers fire on their own while you watch the wave either hold or break through. There is no clicking during combat and no reflexes involved. Anything you get wrong, you got wrong while you were thinking.

You begin with 200 gold and 20 lives, so the opening decision is already a real one: enough for two Thorn Spires, or a single Wind Vortex with 50 gold left over. Every enemy that reaches the wall costs one life. Lose all twenty and the run ends; clear wave 60 and you have won the map.

02  Four towers, four different jobs

The four towers are not cosmetic variants of each other. Each one answers a different problem, and the prices sit close enough together that picking between them is a genuine trade rather than an obvious upgrade path. Each tower also upgrades twice, and the tiers move more than damage — range and fire rate climb with them, so a tier-3 tower covers a different stretch of the path than the tier-1 you placed there.

• Thorn Spire — 100 gold, and the only tower with no trick at all. Straight single-target damage: 25 a shot at tier 1, 120 at tier 3, with the fastest fire rate in the game. When one specific thing has to die, this is what kills it.
• Root Snare — 100 gold, and it barely damages anything directly. Instead it slows everything inside its radius, 30% at tier 1 and 60% at tier 3, and burns it with damage over time. It is the cheapest tower, and it is the one that makes the other three work.
• Crystal Prism — 125 gold. Chain lightning: it hits one target and then arcs to the nearest others in range, two extra targets at tier 1 and four at tier 3, each taking a fraction of the hit. Built for crowds rather than for a single large enemy.
• Wind Vortex — 150 gold, the most expensive, and the only tower that does not want to kill anything quickly. It knocks the enemy it hits backwards along the path and deals half damage to everything else nearby. What it really buys you is time: an enemy pushed back is an enemy standing in front of your other towers for longer.

03  Sixty waves that are the same for everybody

This is the part that separates Thornwall from most browser defense games. The waves are a fixed, hand-written table, sixty entries long. Wave 12 is the same wave 12 every time you play it, for you and for every other player. There is no randomised spawn, no procedural map, no run modifier, no seeded variation — nothing in a run is left to chance. Your score is therefore a measurement of what you decided and nothing else. You cannot reach a high wave count by being lucky, and you cannot lose one to a bad draw.

What changes across the sixty is arithmetic and composition. Each wave multiplies enemy health by another 8% and enemy speed by another 2% over the wave before it, so by wave 60 enemies carry about 5.7 times the health and 2.2 times the speed they had at the start. Composition escalates in steps rather than a smooth ramp. Waves 1 to 9 are Voidlings only and meant to be survived. Wave 10 is your first Void Titan: a boss with 2,000 base health and a 100-gold bounty that moves at a sixth of the pace of a Voidling, escorted by a crowd of lesser enemies. Boss waves land on 10, 20, 30, 40, 50 and 60 — six of them, and none of them optional.

Two waves change the rules rather than the numbers. Wave 15 introduces Breachers: 300-health brutes that shrug off half of any slow you apply. Wave 25 introduces Wraiths, and Wraiths are the important one — completely immune to slow, and moving at nearly Voidling speed. A wall of Root Snares, the strategy that carried you through the first twenty waves, does nothing at all to them. From wave 25 on, the defense has to include towers that deal direct damage to a fast target you cannot hold in place. Every player meets that wall at the same wave.

04  Scoring, and why hoarding gold costs you

Your final score is built from four parts: 100 points for every wave you survived, 50 points for each of the 20 lives you still have when the run ends, 200 points for each Void Titan you killed, and an efficiency bonus of up to 500, calculated from the gold you were still holding at the end divided by every coin you earned along the way.

That last part quietly changes how you play, because the denominator is everything you ever earned — not what you have left. Spending gold does not shrink it. The consequence is blunt: finishing with a large unspent pile is the same mistake as dying with unused lives. Both mean you were holding resources that could have been towers on the path. The game prints the theoretical maximum as 8,700, which requires all sixty waves, all six bosses, and none of your twenty lives lost.

05  The score card, sharing, and the leaderboard

When a run ends you get a score card rather than a menu. It shows the wave count, the final score, a small diagram of where you placed each tower along the canyon and how far each one was upgraded, and a breakdown of how many of each tower type you finished with. It is a record of the shape of your defense, which turns out to be more interesting to look at than the number.

There are three ways out of that card. Copy Link puts the game address on your clipboard. Save Image draws the whole card to a 1200 by 1400 PNG and downloads it, named for the wave and score, so it works anywhere you can paste a picture. Share hands a message to the native share sheet on your device if it has one — something like "I held the Thornwall for 34 waves — score 5,180" — and falls back to copying that text plus the link.

The card also submits your run to the leaderboard, which keeps the top 100 scores. Your display name comes from a fixed list of 230 fantasy-flavoured names and you can reroll until you get one you like; there is no free-text field, and the server rejects any name that is not on the list, so the board cannot fill up with junk. There is no account behind it. What is public is a name, a score, a wave count and the tower types you leaned on, and nothing else.

06  Controls, hardware, and the limits worth knowing

Everything is a click or a tap. Pick a tower type, click an empty node, and it is built; click a placed tower to upgrade or sell it. During the watch phase you can drag the view along the canyon and toggle a 2× speed button, which is worth using on the early waves when little is happening and worth switching back off when a Void Titan walks in. The M key mutes the sound, which is synthesised live in the browser rather than streamed from a file. There is no pause button and no keyboard shortcut for anything except mute, so a run is a sitting rather than something you dip into.

It is built desktop-first: a 1280 by 720 play area, best on a laptop or a large tablet held sideways. A phone in portrait gets a rotate notice instead of a broken layout, and the run will not start until the device is turned. There is one map and no difficulty setting — the sixty waves are the sixty waves. If your system is set to reduce motion, the game respects it and steps back the camera drift, screen shake and particle effects.

Thornwall is free, and it is supported by ads that appear on the title, score and leaderboard screens. There are none during a run — the canyon you are defending is never covered by one.

07  Questions people ask

Is Thornwall free, and do I need an account to play it?

It is free, and there is no account, no sign-up and no install — the game loads in a browser tab and you are playing. It is supported by ads on the title, score and leaderboard screens, never during a run.

How is the score in Thornwall calculated?

Four parts: 100 points per wave survived, 50 points for each of your remaining 20 lives, 200 points per Void Titan killed, and an efficiency bonus of up to 500 based on the gold you finished with as a share of all the gold you earned. The game lists 8,700 as the maximum possible score.

How many waves does Thornwall have, and is there an endless mode?

Sixty, and no — the wave list is fixed and finite, and surviving all sixty ends the run in a victory rather than looping you back to the start. Every tenth wave is a boss wave, so there are six Void Titans between wave 1 and the end.

Why have my slow towers stopped working?

You have met the Wraiths, which appear from wave 25. Wraiths are completely immune to slow effects, so a defense built on Root Snares alone will watch them walk straight through at close to Voidling speed. The answer is direct damage from Thorn Spires or Crystal Prisms rather than more crowd control.

Can I save a run and come back to it later?

No. A run is one sitting — nothing about an in-progress game is stored in your browser, so closing the tab ends it. Only two things persist locally: whether you have seen the first-run message, and whether you muted the sound. Posted leaderboard scores are stored on the server.

Does Thornwall work on a phone?

It is designed for a desktop-sized screen and works on a tablet in landscape. A phone in portrait shows a rotate notice instead of the game, and the run is paused until the device is turned sideways. Touch input is supported; the tap targets for build nodes are enlarged on touch devices.

08  More from the shelf

• Tilewright — Draw seven tiles. Outword the AI.
• Chess — Beat the engine. Post the win.
• Dominoes — Match the ends. Block them out.
• Backgammon — Roll the dice. Race the engine home.

Browse every app in the catalogue →