From the recently released Magic Book of Spells, seems to pull mainly from the Greek and Runic alphabets. I used shorthand for the more annoying letters. Below is the closest Unicode equivalents for all your Mewman word processing needs.

⟠ ⴵ L ◇ ͟□ △ J ⟐ x ߃ ʒ ̅□ ᔭ ᛉ ⟟ ▷ ꖴ ̷ ̸ ᛯ 1 ᛓ ᐁ ᐁ {) ⧋ △

