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Beckoner

Bonus: All Invocations will summon twice the original number of creatures. Summon Invocations cost 1 Phrase less.
Creatures from all Invocations become immune to the Abjurationability of Paladins (who could otherwise destroy any creature that is their level, and deal raw damage to any equal or greater level creature)

Penalty: The chanter's summons are smaller and have reduced Health and Duration.

Skald

Bonus: Offensive Invocations have reduced cost of -1 Phrase. Weapon Critical Hits have a 50% chance to grant +1 Phrase.

Penalty: Non-Offensive Invocations have an increased cost of +1 Phrase.

Troubadour

Bonus: Linger for Phrases is increased significantly (this means that as one phrase ends and another starts, they overlap for a little while giving both effects). 
Gain "Brisk Recitation" (Modal Abilities) that increases the rate that phrases elapse, but removes the linger. 

Penalty: All Invocations have an increased cast cost of +1 Phrase (Chant)

Assassin

 Bonus: Gain Assassinate passive. From Stealth, attacks receive +4 Penetration, +25 Accuracy and +50% Critical Hit Damage.

 Penalty: All Damage received is increased by 15%

Streetfighter

 Bonus: -50% Recovery Time +20% damage when the street fighter is Flanked or Bloodied. +100% Weapon Crit damage when the street fighter is both Flanked and Bloodied.

 Penalty: +20 Recovery Time when the street fighter is neither Flanked nor Bloodied.

Trickster

 Bonus: Learns Arkemyr's Dazzling Lights. Gains access to select illusion wizard spells at power levels 3,5,7 9.

 Penalty: Sneak Attack only deals +20% damage