Two fortresses, a few roads. Free waves of footmen march out of both on a timer and walk their road until something stops them. Bring their fortress down and the map is yours.
Gold is the whole game. It ticks up on its own, the same rate for both sides, and every coin goes one of three ways.
Train buys a hero. Heroes are the only troops you buy - the waves are free and arrive anyway. Each is bought once, and when it falls it waits out a revive and then marches again for nothing. Only one of each can be on the board at a time.
The Ogre is a wall with a club. The Golem throws boulders from behind the line and its stone lands on a group. The Reaper catches a whole knot of men with every blow. The Warhound is fast and built for their heroes. The Catapult is not a hero - it is slow, helpless against troops, and outranges every tower in the game, which is what makes it the answer to one.
The Knight is the other thing you buy, and unlike a hero you buy it again and again. It is nearly twice a footman's pace, so it arrives ahead of the wave and crosses the ground to a rank of archers before they have shot much - but it is not a hero, and a line that is standing and ready will kill it.
Where a hero marches is your decision. It goes to whichever lane is selected when you send it, so a hero that has just fallen is also a chance to put it somewhere else. Watch the strip along the top: ready means it is waiting on you.
Build spends on something that stands. Arm a purchase and every site you can use lights up; tap one to raise it there. Foot soldiers cannot realistically break a tower - that is what catapults are for.
An arrow tower shoots fast and flat, reaches furthest and is the better shot against one target at a time. A cannon tower is slow and heavy and its shot lands on a group - it is what answers a crowd, and it hits their heroes and siege engines nearly twice as hard. Which one a road needs is the decision. The two sites at your own gate, marked gate, take towers only - they are the last thing between a lost lane and your fortress.
A barracks sends an archer out to join every wave that passes it, for as long as it stands. Each one after the first costs more, and each one you run takes 1.5 gold a second out of your income - so a sixth barracks has to be worth more than the coffers it eats. One that is overrun stops paying entirely, so put them on road you are holding. Watch the rate beside your gold.
Upgrade is gold that never walks onto the road and never dies either. Weapons and Armour lift everything you field, four levels each. Coffers raises your income for the rest of the war. Barracks adds another archer to every garrison. Towers makes yours shoot harder, then throw stone, then shoot half again as often.
Upgrading your fortress lifts everything you field by 30% and then 65% - the free waves too - and unlocks the catapult. Your fortress also throws catapult stone at anything that reaches it. You can see how far the other side has got without being told: each tier puts up another curtain wall, more corner turrets, roofs on them and a gatehouse.
Pick a lane from the buttons above the shop, or tap a road. Everything you send goes there until you change it.
The opposition plays from a written plan, and the map draws a different one each game - read the line under the map's name before you press Start. The difficulty you choose in Campaign decides how well that plan is carried out.
Drag to scroll, wheel or two fingers to zoom, Map for the whole board, Pause or space to stop the clock.
There are three campaigns. The Greenlands is where it starts; The Ashlands is burnt country with meaner terms; The Frostmarch is the far north and the hardest ground in the game.