battle points ?

[DeletedUser27700]

Yer, but i mean… all the times i have attacked and lost all my units then i didn't get any BP. So are you sure?

There is one scenario where you wont get any BP.

If you send attacks by sea without Light Ship escorts, and run into a defending ship.
Even 1 Bireme would kill all of your transports and the troops on them, with you scoring no BP at all.