find the code!

HA! you thought i would just let him go that easily? no way!
now you need to figure out the MUDGOOSE DOOR CODE
a four digit code that you will never guess!


in fact because you are obviously so stupid iv even included my secret notes, im that cofident you wont be able to figure it out, plus some of the letters are in my secret code


doorcode (4 digits):



first correctly answered by Koda
also answered by Percy




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