<p>Here's what I believe...
</p><p>Fugitoid reveals that he actually helped to create the Heart of Darkness, either that, or something he says causes the Turtles to loose their trust in him.
</p><p>The Triceratons intend to destroy Earth just like before, only this time, the Turtles receive aid from all their allies in space - The Salamandrians (Mona Lisa and Sal Commander), the Utroms, The Aeons, The Daagon, and maybe even Tokka.
</p><p>It is an intense space battle, in the end, the Fugitoid sacrafices himsefl to destroy the Heart of Darkness, just like he did in the 2003 series; and the Team is reuinted with Master Splinter and their friends.
</p><p>Maybe at the end, Mona Lisa may choose to stay on Earth for a while to see what Raph's home is like.
</p><p>Once the Space Arc is finsihed, the remainder of the season will deal with the Turtles finding Karai and defeating Shredder once and for all.
</p><p>That's my theory.
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