(UPDATE!) Make sure you pick up version 1.1 this is much easier and has a difficulty setting! Thanks!
This is my entry for the Scrolling Shooter Challenge - Deep Sea Encounter (name changed from Alpha Whisper3)
Story - Creatures are invading the Earth from the sea bed and your submarine is the only ship available to challenge them. Unfortunately you have no weapons! Only your shield can protect you. Make your way through waves of enemies and defeat the boss!
Controls - Arrow keys - move. Ctrl - Shield. Escape - quit game. You can also use a control pad.
Use your shield to bounce bullets back towards the enemies. Be careful though as you any have a limited shield charge. If your shield runs out, release the shield button to recharge. Collect Red power-ups to increase your speed. Collect Blue power-ups to increase your shield power.
Tips -
On the first level, head towards the middle in between the fish when they split. This will allow you to collect the power up.
Getting close to enemies before they fire is an easy way to rebound their shots but make sure you have enough shield available!
Colliding with enemies or the landscape will destroy your sub regardless of whether the shield is active.
Collect red and blue power ups as much as possible they will really help.
If you find it too difficult try using a gamepad to control the sub instead.
Cheat Mode - press 'R' to jump to the next level!
Link to Challenge
Link to post mortem