Titanic Plain (タイタニック・プレーン,Taitanikku purēn?) is the fourth area of Sonic and the Black Knight. A vast hinterland of long grasses and Druidic monuments beneath a boundless blue sky, the plain is still home to some of the townspeople—as well as giant green trolls. This area holds many shattered ruins of a past megalithic civilization, and has become a popular tourist attraction in the present day. After King Arthur turned evil, however, the Titanic Plain became the place where the giant lumbering trolls would transport captured people from all over the lands in the world of Camelot too, making Titanic Plain the epicenter for much of the kingdom's suffering.
Amidst the flowing grasses and stony outcrops roll immense wooden city-wagons, pulled by teams of enslaved trolls. These wagons tend to fire massive harpoons in Sonic's direction, and several missions require the player to rescue the villagers imprisoned within. At the end, Sonic will encounter Sir Gawain.
In Deep Woods, Sonic was given three tasks by Nimue, to complete within three days as her condition to help him defeat King Arthur. After completing the first task (freeing the prisoners in Camelot Castle), Sonic and Caliburn come across a crying child in the woods. The child explains that her parents, along with the rest of her village, have been captured by a dragon and are being held within Crystal Cave, presumably on their way to becoming snack food for the beast. Never one to pass up a chance for heroism, the hedgehog promises to free the villagers in spite of Caliburn's objections that this will cause them to fail to fulfill Nimue's quests in time.
Titanic Plain is thus essentially a thorough route; Sonic only comes to the area because it's the fastest path between Camelot and Crystal Cave. However, the Blue Blur's progress is impeded by the abrupt appearance of Sir Gawain, who has finally tracked Sonic down under King Arthur's orders. The pair battle inside a Druidic henge; after losing the fight, Gawain attempts to take his own life to remove the stain on his honour, but Sonic confiscates the echidna's twin blades. He then races off to Crystal Cave in order to save the townspeople.
Items which can be acquired in the Titanic Plains missions include:
Rusty Helmet, Bronze Dagger, Steel Dagger, Vial of Calm, Carnation, Herb, Ace of Spades, Chain Bracelet, Wooden Belt, Medal of Sonic, Medal of Gawain, Arthur's Legend 2, Blue Ring, Broken Lock, Troll's Eyelash, Antidote, Superior Antidote, Bright Red Ribbon