| Instructions |
| Keys | 1-9 selects a Tower & 0 deselects. U upgrades the selected Tower. S sells the selected Tower. Space to toggle pause. N Sends the next level early. |
| The Goal | Creeps enter from the top and from the left. You must stop them from reaching the other side or you will lose lives. You start with 20 lives, and when they are gone the game is over. |
| The Pieces |  Towers are used to attack creeps and also to block their path. You buy a Tower by clicking on its image and then clicking somewhere on the map. There are 9 different towers to choose from, each with different abilities. Towers can be improved by buying upgrades. |
| The Money | Gold is earned by killing creeps, especially the boss creeps which come every 8 levels. You can spend Gold on buying Towers and upgrading them. SPAWNLET creeps do not give gold. |
| The Levels | Each level, or 'wave', contains 20 creeps (10 on easy) and they arrive every 25 or so seconds. They cannot be stopped. Your only defense is to purchase Towers to attack them. Some waves have special abilities like FAST or FLYING. Also, after every 8th wave is a BOSS wave that is especially hard to kill. |
| More Help | If you have never played a Tower Defense before try the Quick Start Tutorial. |
| Friends | When you submit a score you can set up a Group Scoreboard so that you and your friends can share scores and bragging rights! |
| Sell Timer | It takes a certain amount of time to sell a tower; this time goes up as you sell more towers. |
Secret Tips: Read the instructions! A highly upgraded tower does a lot more damage than many level 1 towers.
Anti-air does what it says on the tin. You can earn a higher score by sending waves early, but be careful not to
swamp your maze! 'N' sends the next level early.