Ars Magica 2

Ars Magica 2 is a magical mod by Mithion. This mod is entirely different from the original, Ars Magica, which was not included in any FTB Modpack. Ars Magica 2 focuses on spellcasting, spells creation/customization, and bosses. Unlike in Ars Magica, AM2 has the power to create highly custom spells which you can tweak to your liking- However Keep in mind that their cost and power will depend on your current Casting Mode (As of 1.2, Casting Mode has been replace by Shape Groups).

Bosses and Mobs
Ars Magica 2 adds a couple new creatures to The Overworld and The Nether, most of them are hostile and fairly tough to kill. Additionally, you can summon highly powerful bosses into the world which will each have a chance to drop their signature item.

Bosses

 * Arcane Guardian
 * Earth Guardian
 * Ender Guardian
 * Fire Guardian
 * Lighting Guardian
 * Life Guardian
 * Nature Guardian
 * Water Guardian
 * Winter Guardian

Mobs (Hostile)

 * Dark Mages
 * Darkling
 * Earth Elemental
 * Fire Elemental
 * Hecate
 * Hell Cow
 * Mana Creeper
 * Water Elemental

Mobs (Peaceful)

 * Dryad
 * Flickers
 * Light Mages

Experience System
Ars Magica 2 has it's own experience system (called Magic Levels), which is used to level up, and gain more Skill Points for spell discoveries along with an increased Mana Pool for spell casting. The experience system is based on when you cast spells; each time you cast a spell successfully (eg: using an offensive spell to damage to an entity), it will give you experience.

When you first cast a spell, you will be awarded a lot of experience but will decrease for every successive cast. There's also a Burnout on the spell, which is generally shown as the red bar to the left of your screen- the higher your Burnout meter is the less experience you will gain, this is to prevent players from increasing their magic level by "spamming" out a single spell. In addition, casting spells will cause you to gain "depth" in certain Affinities- This can be view in your Occulus or by the appearance of small icons generally to the bottom right of your screen.