"Doodle" monsters look like hand-drawings made by a child with awkward lines and a hand-made painting, with the addition of a white border around the drawing, making it look like it was cut out of a sketch book.
So far, the revealed "Doodle" monsters are all Dinosaur-Type. Usually, the names of dinosaurs are written in Katakana in Japanese; however, the names of the "Doodle" dinosaurs are written in Hiragana instead. Also, the Japanese words are all written in Hiragana as well instead of the more "advanced" Kanji characters. These writing patterns reinforce the childish vibe of the archetype and support the concept of artworks being done by a child.