Haskell, 138 bytes
m x=do h<-readFile"a" return$take 225.drop(225*mod x 2)<$>find((==h).hash.pack)(replicateM 425"/\\|_- ") This is a bit of a hack. I am bruteforcing the SHA256 hash fromof the concatination of the two minecraft texts, and then splitting them apart and choosing the appropriate text based on parameter x. This is of cource very impractical and cannot be computed in real time, and there may even be collisions along the way for all I know.
Because Haskell cannot have the ASCII representation of that hash in a string, I am reading it from a file called "a", and has therefor added 32 bytes to my score.
- readFile and pack is from Data.ByteString.Char8
- hash is from Crypto.Hash.SHA256
Explaination:
replicateM 425"/\\|_- " Creates a list of every combination of the letters "/\|_- " on 425 letters (the length of both minecraft texts combined)
find((==h).hash.pack) Pick the first one that matches the hash
take 225.drop(225*mod x 2) The first text is 225 letters long, the other one is exactly 200.