Secret Message from the Junta

You have received the following secret message from the Junta:

We attempted to send you four puzzles whose answers are a coded version of the true identity of the MathCamp Secret Police. If this identity can be discovered, it can be used to destroy them once and for all. Unfortunately, these puzzles were intercepted by the Secret Police, so you do not have them. However, just in case you manage to solve these four puzzles anyways, here is the key to decoding their answers to find the true meaning of MCSP.

  1. If the length of the string is divisible by 9, append STIC to the end. If length is divisible by 3 but not divisible by 9, append CE to the end.
  2. Replace the first consonant in the string with P.
  3. Replace any E next to an N with S, unless there are two such Es in the string, in which case you replace them both with I.
  4. If the string contains an animal as a substring, replace the last two letters of the string with AL.
  5. If the letters D and O both appear in the string, replace the first instance of each one with A.
  6. If the last letter of the string is a consonant, replace every E in the string with a C.
  7. Caesar-shift the third letter of the string forward by 16.
  8. Whenever another vowel occurs immediately after an A, replace the vowel with N.
  9. If the string contains a substring which is the full name of a chemical element, replace that substring with BAL.
  10. If the length of the string is prime, replace the first letter with the last letter.
  11. Replace every every O with G and every W with N.
  12. If the string starts with two consonants, swap the fourth and fifth letters of the string. If the string contains a substring of five letters which anagrams to give a kind of body of water, replace the fourth and fifth letters with IA.
  13. If the fifth letter of the string is a consonant, replace it with U.
  14. Change exactly one letter of the string to turn it into an English word. The word should not be an adverb.