There is no official "Version 803" widely recognized in the Angry Birds PC changelogs. The number likely refers to one of the following:
All three original episodes are included:
The recent "updated" interest stems from rumors and community discoveries, such as:
The 8.0.3 update provides a significantly expanded experience compared to the older official PC versions, incorporating years of mobile-side development:
Then, text appeared at the bottom of the screen. It wasn't the usual "Level Complete" jingle. It was a dialogue box, the kind seen in old RPGs.