https://www.purezc.net/index.php?page=quests&id=150
This quest has, at one point, a Death Mountain area with flashing lightning. There is a recommendation to disable the transparent layers if one is prone to seizures. However, this quest was made in 2.10, and in 2.5+ there is no such option. This might ruin the aesthetic if used in other quests but everyone who made quests in the 1.92/2.10 era knew that the user could do this, so it's not unexpected.