潮汐战线 Tidemark

Tidemark (潮汐战线, "where the tide leaves its mark") is a classic turn-based strategy game in the spirit of Advance Wars. One map, a few armies, one turn each: build units, capture cities, take the factories, and push the front line square by square to the enemy headquarters.

The rules are easy to learn: units counter each other, terrain decides attack and defence, and money comes from the cities you hold. The hard part is the choice you make every turn. Capture or build? Hold the bridge or go around? Use your commander's power now, or save it?

What's in it

• 33 units on land, sea and air. Infantry capture, tanks advance, artillery fires over mountains, fighters take the sky, warships close the sea lanes, and transports land troops where nobody expects them.
• Four nations and 29 commanders, each nation with its own commanders and technology. A commander with a full meter can use a power that turns a battle in one turn.
• A campaign in six acts: one story told mission after mission, with cutscenes.
• 24 skirmish maps for 2 to 4 sides. Each side can be a player or the computer, and sides can form alliances.
• Fog of war, on by default in free play, so scouting and ambushes matter.
• Research: put part of your income into technology to outclass the enemy late in the game.
• A codex with every unit, terrain and commander, and who counters whom.
• Ten languages: Simplified and Traditional Chinese, English, Japanese, Korean, Spanish, French, German, Portuguese and Russian.

Several people can take turns on one device, with keyboard, mouse, touch or gamepad. It's a cartoon war between pixel-art armies, with no blood.

How it was made

Tidemark was made by CocoSgt (赛博禅心) with Claude. The repository's commit history credits Claude Fable 5.2 for the first game packages and Claude Opus 5.5 for the release builds and the balance updates that followed. The whole game (code, maps, text and art) is open source under MIT, and it also ships in the DSH Game Store for DeepSeek Harness, with a Chinese manual.

Credits

Made by CocoSgt, MIT licence. The game font is Fusion Pixel Font (SIL Open Font License 1.1). Played here from the author's own site.

How a battle works

1. Build units at the factories you hold, with the money your cities earn.
2. Capture cities with infantry to raise your income and cut the enemy's.
3. Push the front line forward and take the enemy headquarters.

Before every attack

The game shows a forecast first: how much damage you'll deal, whether the defender can counter-attack, and who counters whom. Read it every time. A bad trade costs you more than a skipped turn.

Unit roles

Role	What it's for
Infantry	Capture cities and factories
Tanks and vehicles	Advance and hold ground
Artillery	Fire from behind the line, even over mountains
Fighters and air units	Control the sky
Warships	Close the sea lanes
Transports	Land troops where nobody expects them

Tips

• Terrain is half the fight. Defend from good terrain, and don't attack into it. Terrain defence is capped at 70%, so nothing is invulnerable.
• Capture early. Every city you take is income every turn for the rest of the game.
• Watch the commander meter, yours and theirs. One well-timed power can turn a battle in a single turn.
• Research pays off late. Put some income into technology if you expect a long game.
• In fog of war, scout before you commit, and use the fog to set ambushes.
• Merging two units keeps a boost, and refunds one if both had it.
• Open the codex at any time to check counters, terrain and commanders.

Controls

Input	Action
Click or tap	Select a unit, building or square
Click or tap again	Move, attack or capture
Keyboard / gamepad	Also supported throughout
Top right of the title screen	Change language