Chapter 4: Overlord Source Matter: The One (This is a Supreme Source Matter, currently located in the Void Tree Inventory).
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The rewards were tempting, but Su Xiao glanced at the Dark Hybrid beginning to reform. A wisp of golden Solar Flame flickered across its remnant body. Seeing this, Su Xiao turned and left without hesitation.
He had previously assumed the Dark Hybrid's three traits—Extreme Blade, Spatial Walk, and Backlash—meant the backlash reflected damage. Now it was clear that wasn't the case. This backlash represented the counterattack from the Daddy-level Original Sin Objects he had sealed.
Su Xiao had sealed six Daddy-level Original Sin Objects. As a result, the Dark Hybrid had seven stages. The first stage was the initial phase, and the subsequent six stages each corresponded to the traits of one Daddy-level Original Sin Object. What was coming now was the trait derived from the "Sun Mask."
He summoned the Lord's Train, letting Bubu Wang, Amu, Beini, and the others board. The train started moving. As for killing this Dark Hybrid—don't even entertain that fantasy.
As for how to enter the Dawn Ruins, Su Xiao didn't necessarily need a key. He had obtained an item earlier in the Wind Sea Continent called the [Dawn Pass].
[Dawn Pass]
Category: Pass.
Effect: Using this item allows entry into the Dawn Paradise (Dark Ruins State).
Description: Go seek the treasures hidden in the darkness, or be buried in the endless abyss.
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As for what to do with the absurdly powerful Dark Hybrid left behind after leaving this place—that was for the other participants to handle. Good things should be shared. The kill rewards for this Dark Hybrid were so generous, how could one hoard them all? They had to be shared.