Clear the first wave.

Clear wave 10.

Clear wave 20.

Defeat the final assault and win the war.

Win with a B grade or better (60 min or less).

Win with an A grade or better (50 min or less).

Win with an S grade (40 min or less).

Bring down the Siege Giant.

Shatter the Wall-Breaker Golem.

Topple the Siege Tower.

Shoot down the Airship.

Destroy the Catapult Fortress.

Land 500 headshots.

Defeat 5,000 enemies.

Run over 100 enemies with vehicles.

Capture an enemy vehicle.

Take off in a helicopter.

Send out the cavalry.

Shoot down 20 fighter planes.

Obtain a legendary weapon.

Fully upgrade the castle.