You can blend the power of your performance and spellcasting.
Prerequisites: Cha 13, bardic performance class ability, able to cast 1st-level spells.
Benefit: You can combine your bardic performance and your spellcasting in two ways.
First, you can conceal the activity of casting a bard spell by masking it in a performance. As a swift action, you may combine your casting time of a spell with a Perform check. Observers must make a Perception or Sense Motive check opposed by your Perform check to realize you are also casting a spell. This uses 1 round of your bardic performance ability, regardless of the spell's casting time.
Second, as a move action, you can use 1 round of bardic performance to maintain a bard spell with a duration of concentration. You can cast another spell in the same round you are using bardic magic to maintain concentration; if you do this, your concentration on the maintained spell ends when you end the bardic performance the spell is part of.
Essentia: Your opponent have a -2 Penalty / Essentia on their Perception check