Secondary Mechanic(S) : The set of mechanics that are not mandatory to beat the game (or some other specified set of challenges). Secondary mechanics are also not tertiary mechanics
Richard Hakem Terrell (KIRBYKID), An indie game designer, video game consultant, tournament organizer, competitor, writer, musician, artist, and teacher), Critical-Gaming Network (Critical-Glossary), Dallas, TX, USA 2007 (updated 2013). http://critical-gaming.com/critical-glossary/, (Ergo - Amer) {747}