  Bugs that persist into releases of video games can have negative impacts on
both developers and users, but particular aspects of testing in game
development can lead to difficulties in effectively catching these missed bugs.
It has become common practice for developers to apply updates to games in order
to fix missed bugs. These updates are often accompanied by notes that describe
the changes to the game included in the update. However, some bugs reappear
even after an update attempts to fix them. In this paper, we develop a taxonomy
for bug types in games that is based on prior work. We examine 12,122 bug fixes
from 723 updates for 30 popular games on the Steam platform. We label the bug
fixes included in these updates to identify the frequency of these different
bug types, the rate at which bug types recur over multiple updates, and which
bug types are treated as more severe. Additionally, we survey game developers
regarding their experience with different bug types and what aspects of game
development they most strongly associate with bug appearance. We find that
Information bugs appear the most frequently in updates, while Crash bugs recur
the most frequently and are often treated as more severe than other bug types.
Finally, we find that challenges in testing, code quality, and bug reproduction
have a close association with bug persistence. These findings should help
developers identify which aspects of game development could benefit from
greater attention in order to prevent bugs. Researchers can use our results in
devising tools and methods to better identify and address certain bug types.
