So my family is driving to our vacation spot this winter (24 hours straight). It will be mostly highway driving, so the scenery isn't going to do it. I'm looking for some apps that will keep me engaged for a long time, not just quick time wasters. Note that the game will have to be playable offline as I will not be using data on the trip. Battery life is not an issue. I am a big fan of RPGs, specifically 'rogue' / dungeon, but I'm open to anything really. Free games are preferred, but if you really think it's worth the money, post away.

As of now I have specifically put aside "Bard's Tale" and "The Quest" but the more suggestions the merrier.