Magriel's M is a term central to tournament strategy. It gives the relation between one's own stack, the antes, and the blinds. This gives a rough idea of how many hands a player can expect to survive before he is all in if he plays no hands.
M = stack: (Ante * nr. players at table + Blinds)
In his book, "Harrington on Hold'em", Dan Harrington presents a zones system based on the M of a player. In each zone, the player's style of play changes because of the pressure on the player. The smaller the M, the fewer complex moves the player is in a position to make.
- Green Zone (M more than 20)
The player is comfortable and can be choosy about the hands that he plays. He can make targeted risks if there is a chance of a large payoff.
- Yellow Zone (M between 10 and 20)
The player is under some pressure and can no longer play conservatively. he must take more risks and more hands to build up his stack.
- Orange Zone (M between 6 and 10)
The player must become more aggressive to increase his stack. He no longer has the chips to make complex moves, since he cannot get the implied odds he needs or put others under pressure over many rounds of betting.
- Rote Zone (M between 1 and 5)
The player is not forced to go all-in or fold every time. He has enough chips for some otehr moves, but cannot wait for a good hand. He must attempt and all-in in any favorable situation, even with marginal hands and especially if he is first in.
- Tote Zone (M less than 1)
The player is as good as eliminated. He doesn't even have enough chips to get an opponent to fold to his all-ins. Nothing short of divine luck can save him at this point.