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Now this, this is how you make an interesting story. Not just the main plot, but even the side-stories had me hooked from start to finish.
The gameplay, I guess you could call it more of an idle than a tower-defense, but it's fun and not very hard to progress if you have the right units. The game has been plenty generous in my experience as well.
It also has PvP, which gives you something to do after you've finished all the content. Nonetheless, the updates and new characters tend to be good, so there's not much to worry.
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