One of the first companions you gain in "Dragon Age: Origins," Morrigan has access to several powerful elemental trees as a mage. Depending on your class, there are two primary ways you can take her: the damage route or the healer route. Like any other mage, Morrigan lacks the essentials needed to withstand direct attacks, so it's not possible to bulk her up as a tank.
Morrigan's Primary Stats
As a mage, Morrigan primarily focuses on two main attributes: magic and willpower. Depending on how you want to build this party member, the attribute you'll focus on will vary. Magic bulks up spellpower and mental resistance, but spells that use heavy amounts of mana demand a bigger pool; that's where willpower comes in. Each point of willpower increases Morrigan's maximum mana, letting her pull off more attacks before running out.
Rather than have Wynne act as the party's healer, you can learn the art from a tome from the Wonders of Thedas store in Denerim, opening the option for Morrigan. As a spirit healer, Morrigan gets a boost to magic and access to new abilities. Unlocking the Revival ability is essential; this lets a fallen party member get back up in the middle of combat, giving you a second chance to end the battle. With Group Heal, Morrigan helps heal some of the wounds of the group. If coupled with the Blood Mage specialization, be sure she stays on the outskirts of battle; the constant toying with her health bars leaves her far too vulnerable to be near enemies.
It's not necessary to focus on specializations; Morrigan can wreak plenty of havoc with the Primal tree. Be sure to unlock the high-level fire and ice spells; having a mixture of Inferno and Blizzard creates devastating conditions for any enemy who dares cross your path. Just make sure to pay attention to positioning if you play with friendly fire enabled; otherwise the elemental damage won't discriminate on the battlefield. For added damage, unlocking Chain Lightning helps with group settings, giving Morrigan an aggressively powerful build.
Blood Mage-Shapeshifter Hybrid
Often a result of tweaking for Nightmare difficulty, hybrid trees can create powerful combinations with incredible results. In Morrigan's case, her natural shapeshifting ability and the Blood Mage tree can give her a major advantage. Using the abilities in the Blood Mage tree destroys enemies but draws health as a resource instead. When she runs low, have Morrigan shift into a Flying Swarm. You must unlock the Master Shapeshifter ability to access this. When you do, she'll regain the health needed to unleash her blood magic once again.