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…

WhyWider and more aggressive. Antes add 900 of dead money to every pot, so steals win more and your M is lower than the blinds alone suggest - both push you to open wider and shove sooner. J-9 suited on the button is a clear steal with antes in.
What happensYou open to attack the dead money.  Antes reward aggression.
Antes change everything in the endgame: they add dead money worth stealing and they shrink your M, so correct play gets looser and more aggressive once antes kick in.

Antes lower your M and add dead money - open wider and shove sooner once antes are in play.