Immortal

Race: Protoss
Type: Ranged Assault Support Walker
Hitpoints: 240
Shields: 100

[source: starcraft.wikia.com]

The Protoss Immortal is a powerful cybernetic warrior formed from crippled warriors.

Before the loss of Aiur, veteran Protoss warriors who had been crippled in battle could volunteer to continue their service by being transplanted into Dragoon exoskeletons. Now, the Dragoons of the past are all but gone. The sacred shrine that was dedicated to the creation of the Dragoons was infested by the Zerg.

The remaining Dragoons have been transformed into Immortals. They are outfitted with twin phase disruptors as their primary attack form; Immortals give critical fire support to legions of Zealots. Their specially hardened energy shields only activate when struck by powerful attacks, but can render the damage of even a Siege Tank irrelevant - unfortunately, this leaves them more vulnerable to the pinprick attacks of lesser foes.

Quotes
# I return to serve.
# It is destined.
# There shall be a reckoning.
# I feel your presence.
# Our cannons shall sing.
# We march to victory.