In the Edain Mod you can recruit Gandalf the Grey in the Citadel at a cost of 3000. To get Gandalf the White you must gain a 2pp Spellbook ability called Gandalf the White. After that he will transform into the White Wizard automatically. As the White Wizard Gandalf gains +50% bonus damage on magic attacks and -25% recharge time for his spells. Both non-Ring versions of Gandalf (the Grey and the White) have the same abilities!
Gandalf is one of the ring heroes of Arda who has access to two different forms when he carries the One Ring. If Gandalf remains a gray wizard, the Ring will corrupt him, turning him into a terrible sorcerer. If you have "Gandalf the White" active from the spellbook, however, Gandalf will overcome the Ring's corrupt powers and use it for good.
Gandalf the CorruptedIf Gandalf acquires the One Ring while being Grey he will use the ring for his own ambitions and become "corrupt". He will weaken allies in his presence and will damage them over time. In this form Gandalf gains AOE attack type. If you purchase the Spellbook spell Gandalf the White while he is corrupted (with the Ring) he won't turn white until he dies and loses the Ring.
This transformation is the result of giving Gandalf the One Ring too early. Without "Gandalf the White" being active, the ring poisons Gandalf's mind, turning him into a black wizard with a horrifying visage. Weighed down and drunk with power, Gandalf the Corrupted will limp around slowly, becoming unable to mount Shadowfax. Any friendly soldiers nearby Gandalf will run and hide in terror from his presence.
Gandalf the Corrupted is a mass slayer of soldiers, but he is heedless of friend and foe. His attacks have an area of splash damage that kills enemy and allied units alike, sending groups of people flying through the air. With his numerous spells, Gandalf incinerates his enemies by powers of flame, lightning, and darkness. Unfortunately, the ultimate price for this power is speed--Gandalf the Corrupted is weighed down so much by the Ring's heavy burden that he becomes an easy target for enemies. The Ring will repeatedly attempt to abandon Gandalf by keeping him stumbling at a slow pace so that enemy units can catch up to and kill him.
Level 5: Gandalf's Words - Gandalf speaks in the Black Speech of Mordor unleashing dark powers. He will become soaked in twisted, dark, poisonous power which increases his armor and speed and will cause nearby enemies to flee in terror. His spells also become more powerful and recharge faster for the duration of the effect.
Level 10: Dark Words of Power - Gandalf speaks the Dark Words of Power. All surrounding units, friend or foe, will be blasted away, enemies will receive high damage, and trees and Ents will be burned to ash.
Gandalf the Challenge Master
If Gandalf acquires the Ring while being White he will use the One Ring for the well-being of all Men. Heroes and units close to Gandalf will be healed. In this form Gandalf takes on a more angelic appearance, glowing with a bright light as one of the Maia. His attacks are far more powerful and he is less burdened by the Ring. Friendly units feel hope with Gandalf the bright in their midst, and Gandalf's powers are directed only at his enemies.
Level 10: Bright Words of Power - The Challenge Master speaks the Bright words of Power that blast away all enemies. Surviving units will run in fear and will have -50% armor. Automatically activates a light sphere which will protect Gandalf from heavy attacks after the words have been spoken.
Gandalf can be given one upgrade:
Gandalf the Grey is a wizard hero who specializes in destroying large numbers of enemy units with his special abilities. However, he is pitiful in one-on-one combat, and is better suited to being set just behind the front lines. Gandalf is ideal for taking out powerful units as he levels up and acquires new spells, but if he runs out of options, all he can do is run and fight. His Word of Power has become famous as the ultimate mass-slaying move as it blasts away all units in a HUGE radius around him, instantly killing most of them.
When you purchase "Gandalf the White" from Gondor or Arnor's spellbook, Gandalf becomes more powerful as a hero, able to withstand magic damage, dealing more magic damage, and reloading his spells faster.
As Gandalf the Corrupted, your Ring hero becomes a madman that's intoxicated by the Ring's evil whispers, gaining a tremendous increase in power at the cost of his speed. In this form, Gandalf is ill-suited for combat; one, because he injures his own friends, and two, because he cannot escape if he is cornered and surrounded. Against enemy units however, Gandalf the Corrupted is devastating, and can be used as a means of pushing the assault forward if your forces are outnumbered. Do not count on him to be as great as he could potentially be however. If you want to see Gandalf's true power, you're better off purchasing "Gandalf the White" from the spellbook and then acquiring the One Ring.
Mechanics in Erebor, Ered Luin, Iron Hills
Summon the Grey Pilgrim to the battlefield.
Gandalf is nothing without his abilities when summoned by the Dwarves. His Explosive Blast should be used on large clumps of enemy units to kill and disrupt. Gandalf's Fireworks should again be used to large groups of enemies as this will have the largest impact. The Burning Pine Cones can be used to inflict fire damage on targets, making him powerful against ents. Gandalf is not present for a long time and so his abilities should be used quickly, without being wasted. As Gandalf's main strength is his abilities, certain abilities like the Witch-King's Soul Disturbance and Lurtz's Cripple will immediately weaken his impact. Used efficiently, Gandalf can have a massive effect on the outcome of a battle and can destroy whole armies by himself.
"Fly you fools!"
"Through fire. And water."
" We cannot tarry!"
"All we have to decide is what to do with the time that is given to us."
"I have thought of a better use for you…"
"You shall not pass!"
"There are other forces at work in this world Frodo, besides the will of evil."
"It's the deep breath before the plunge."
As Gandalf the Corrupted;
"Don't take me for some conjurer of cheap tricks!" --Selected or attacking
"One ring... to rule them all..." -Selected
"The ring... has awoken..." -Selected
"You shall not pass!" -Gandalf's Words activated, or attacking"Return him... to me..." -Attacking