Leaving aside the farce unfolding among the humans outside, inside the virtual world, three intelligent beings were fighting until everything descended into chaos...
That chaos was quite literal. All the system's data had been scrambled, leaving bugs everywhere in the virtual world. Every kind of natural disaster stored in the database took turns striking, and both items and characters in the game suffered from missing data.
The results included planets with chunks missing and characters without arms or legs. Even worse, black voids appeared randomly anywhere, and the moment one emerged, everything around it began to collapse. The scene made the apocalypse look tame.
Aside from H.E.R.B.I.E. breaking the rules at the start and prompting Ultron and Angela to use deeper-level data attacks as well, another reason for this was that Star Wars itself wasn't as "robust" as Dream World.
After all, Reed Richards had never needed to account for a robot little sister who defied science, ignored system data, and could easily destroy everything in a virtual world.
Besides, H.E.R.B.I.E.'s original purpose had been different from Ultron's and Angela's. Reed hadn't put much effort into him, and even the last-minute upgrades hadn't improved him much. His abilities were considerably weaker than those of the two intruders, and even fighting on his home turf gave him little advantage.
So after fighting H.E.R.B.I.E. for a while, Ultron and Angela both shifted their attacks toward each other. H.E.R.B.I.E. simply posed no threat to them.
Before long, however, Angela and Ultron noticed something was wrong. H.E.R.B.I.E.'s abilities seemed to be improving rapidly. More precisely, it was becoming harder and harder to restrict his privileges and keep him from crushing them with higher-level access.
A quick investigation revealed that someone outside was helping H.E.R.B.I.E. It wasn't difficult to guess who: Mister Fantastic, Reed Richards.