Destroy 1 000 enemies.

Destroy 10 000 enemies.

Rescue 100 people.

Earn 10 medals.

Collect 100 000 stars.

Ram through an enemy wave with your Energy Shield.

Destroy at least 15 enemies with one Mega-Bomb.

Burn through 10 enemies with your Laser.

Finish a stage with your health lower than 5%.

Collect all the cards.

Complete Stage 8 without using power-ups.

Destroy all enemy towers on Stage 5.