Type: Substitution
CIPHER: First column and firs row contains numbers while the rest is letters)
Example: 5x5
✴1 2 3 4 5
1|A|B|C|D|E|
2|F|G|H| I |K|
3|L|M|N|O|P|
4|Q|R|S|T|U|
5|V|W|X|Y|Z|
Ciphertext: 3,2 3,4 3,3 4,3 4,4 1,5 4,2 or
Ciphertext: 32 34 33 43 44 15 42
Plaintext: MONSTER
