Features: cheap and convenient

Uses: exploration, tourism, scientific experiments, advertising, extensive.

submarine

Features: Good concealment.

Use: Invisible to give the enemy a blow.

warplane

Features: There is usually no need to escort and suppress the support aircraft of the other side's air defense system when performing combat missions.

Use: directly attack the enemy.

space plane

Features: Reusable.

Uses: Space exploration and satellite repair.

helicopter

Function: Hover operation

Use: specifications