Part: Part Nine - Inflection Points: M, Q & the Zones

What antes do to M

Pre-flop
Blinds 400 / 800 (100 ante)Pot 2,100 (2.6 BB)Your M = 9 • Orange zoneBTNJ♦9♦● 18,900 (23.6 BB)YOUantes in playSB● 18,900 (23.6 BB)posts 400 (0.5 BB)BB● 18,900 (23.6 BB)posts 800 (1 BB)D

Antes (100 each, nine players) are now in play. Folded to you on the button with J♦9♦ at M 9.

With antes in, folded to you on the button with J♦9♦. Compared to a no-ante game, antes make you…

WhyNine antes of 100 drop 900 into the middle before anyone acts, so a successful steal now wins far more than the blinds alone - and that same drain means your real M sits below what the 400/800 blinds suggest. J-9 suited on the button clears the bar for a steal easily once that extra dead money is there for the taking.
What happensYou open to attack the antes from the button. A pot fattened by antes rewards the aggressor - the same hand you might fold with no antes becomes a clear steal.
Antes flip the endgame toward aggression - more to steal, less M to sit on. Once they're in, correct ranges loosen and the button becomes a printing press.

Antes do two things at once - they pile dead money into every pot and they quietly shrink your M. Both point the same direction: open wider, jam sooner.