Credo is a strategy card game designed by Chris V. Gidlow, and first published by Chaosium in 1993. It is set in the early history of the Christian Church and is based on hypothetical alternatives to how the Nicene Creed, its contents, and what would be seen as heresy might have been decided upon by a series of Ecumenical councils and the influence of the Roman Emperor (particularly Constantine I). Considered by many game reviewers to be highly playable.