Board Thread:Questions and Answers/@comment-27327020-20160404174206/@comment-27330113-20160807175957

Undertale has two sets of stats: internal stats and CHECK stats. Internal stats are not made visible within the game itself and are only found by looking in the game's files. These are the stats that influence how much damage a character can do and how much they can take, just like traditional RPG stats. CHECK stats are, as the name implies, the stats seen when using the CHECK option on an enemy. These stats have no affect on the gameplay whatsoever, and exist only to show how strong one character is compared to another. While they are very clearly shown to be non-linear, they do allow us to see which characters are stronger or weaker compared to other monsters. They're also canon to the world, as Chara makes mention of them (it's possible Sans does as well, though I do not remember exactly where if he does)

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