Nope. There are various levels of AI that can serve as opponents, including an AI and game mode that sends waves after waves of enemies until you kill enough of

Nope. There are various levels of AI that can serve as opponents, including an AI and game mode that sends waves after waves of enemies until you kill enough of its stuff that it sends the final boss you must defeat to win the game. There's also a campaign that introduces units progressively. I'd recommend to start there.