He is both a liar and a bullshitter. He intentionally lies

And he bullshits which of course are a form of lying. Someone who exaggerates about the size of fish he caught and release - or the one that got away is charming - this is not who Donnie D is. He does it for advantage as a bully would. In A harmful way.

He bullshits about his athleticism, his words and lies about literally everything.

It’s safe to call him a liar.