This article is from the Magic: The Gathering Rules FAQ, by Patrik Linell (pls@claymore.nu) with numerous contributions by others.
No. When choosing a creature type, you must choose an existing
creature type. "Elf works", "Pixie-Queen" works, "Myr" works, "Blinkmoth"
works (tokens count as existing creature types), but neither "blue",
"artifact" or "Recidivist" work.
 
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