Defend towers.

Stand atop your tower and launch boulders at the approaching soldiers. Idea started while playing Ziggurat.

Hold X to charge up the power in your boulder, release to throw it.

Catch fish for money and beat those bloodthirsty sharks back from your small boat on the ocean.

From the start, you can catch any fish by clicking on it and knock sharks away by clicking on them as well. Shop upgrades and items will aid you in both areas. Eventually you'll find killer whales and they don't care whether you're shocking them or hooking them, you need to do serious damage to keep them away and that's only possible with the anti-shark items.

Shop rundown:
Nets slow fish down

Electric Rods allow you to fish by holding down the mouse button

Trash Traps are cheap and do little damage

Sea Mines instantly kill a shark/orca and damage neighbors.

Shark Hunter XS's make great long-term additions to your defense

Also, I don't support shark or whale violence. They're cool animals, don't hurt one unless you or another person are in serious danger and have no other option.

Based on a Kickstarter supporters idea:
"Player is on a boat surrounded by sharks. Fish to make money to buy anti-shark devices. Fishing tower defense!"

As you might tell from the name, this is a new minimalist kind of tower defense app. You have a single set of unique turrets which can only be placed at three locations. Click, drag and drop to move your turrets at will. Dropping it onto another turret will make them swap places. While carrying a turret, it will fire at just one third its normal rate.

Each turret is best at dealing with a specific enemy type. Place and move them with a keen eye and a swift hand to protect those nips!

EXTRA CHALLENGE: invent a plot for this thing and post it in the comments. May the best person win.

I was going to make some sort of shmup tower defense thing where you place towers/options/multiples around the screen and try to avoid being killed by waves of enemies without having weapons on the player "ship" itself, but then I didn't feel like making waves of enemies and noticed that I had already basically made potential obstacles in making the towers.

The red bar draining at the top indicates when the next tower will spawn. When it empties, a new tower is placed at your current position. After another few seconds, the tower goes into "active" mode. Once active, the tower fires bullets at a set rate. Survive for as long as possible and set that high score!

Arrows - move
Shift - slow movement speed