You receive Command Undead or Turn Undead as a bonus feat. You can channel energy a number of times per day equal to 3 + your Intelligence modifier, but only to use the selected feat. You can take other feats to add to this ability, such as Extra Channel and Improved Channel, but not feats that alter this ability, such as Elemental Channel and Alignment Channel. The DC to save against these feats is equal to 10 + 1/2 your wizard level + your Charisma modifier. At 20th level, undead cannot add their channel resistance to the save against this ability.