Anyone willing to help with AI

I'm making an Aeon of Strife type of game for anyone that doesnt know your a single hero rushing with computer units trying to destroy the other town.

AI is simple but i dont know how to do it. all i need to do is make it spawn some units follow a path made by terrain and doodads and to try and kill the other town.

Can anyone help me make this AI?

In this case i suggest a trigger-based AI.

Could someone please explain trigger based AI because i dont understand how i use it

You use triggers... like the Unit - Issue order, and a whole load of em...