God Stat
A God Stat is roleplaying gamer slang for a character statistic with a particularly unbalanced effect compared to the other characteristics. It is the opposite of a Dump Stat. God stats are often accidentally created by GMs as a result of their house rules; sometimes, however, they are present in the system RAW. In combat-related games with point-based character generation, for example Inquisitor (a Warhammer 40,000 RPG and skirmish-level wargame), it is often a stat that governs the number of attacks or actions-per-round the character is allowed (in this case, Speed, a stat derived from Initiative).
Dexterity is the most common god stat, often allowing one to hit more, be hit less, and move faster.
In the game Mekton, Reflex is the God Stat because without it you simply can't do anything awesome (like be a Mechwarrior, which is what the system is built around) and you will just fall over a lot and get hit all the time (like your average grunt suit pilot - NPCs should have low Reflex.) It's closely followed by Intelligence and Education, which govern your number of skill points. High numbers of skill points allow you to add a fuckton to dice rolls, since they're nearly all opposed checks using Reflex and at least one skill.
In the Fallout series of games, the undisputed god stat is intelligence. Having a high intelligence gives you the most skill points, so it would be retarded to neglect it.