Super Plasma Bolt - hold down the UP-key for 2 seconds till you hear
 "Charge up". Then press fire. This will cost you one hit.

 Fireballs - move six or seven times from left to right and then press
 jump. This will cost you one hit.

 Shield  - move six or seven times from right to left and then press
 jump. You get a different colour and a shield appears. Last for a
 very short time.

 Invulnerability - hold down the UP-key for 2 seconds then press the
 DOWN-key. You will blink and be invunvulnerable for a very short
 time.