Heel Face Revolving Door/Playing With

Basic Trope: A character bounces between hero and villain.
 * Straight: Eva joins Alice and Bob's fight against The Empire, but betrays them later on... only to flip back again later. And again when they meet The Dragon. And after the dragon pulls You Have Outlived Your Usefulness...
 * Exaggerated: Eva changes sides Once an Episode
 * Justified:
 * Eva has a Split Personality; one with The Empire, the other with them, thus causing her switch over.
 * Alternately: Eva is really indecisive.
 * Alternately: Eva isn't loyal to either side. She joins whichever side is helping her agenda.
 * Alternately: Eva is a mercenary.
 * Alternately Alternately: This conflict is not a simple "vs. The Empire" fight, despite the fact that The Empire is fighting, but is very morally gray. The truth is, Eva is the most black and white character there, but the shifting ideals, policies, and harm each is doing causes the person who benefits from Eva's help, and who's help benefits Eva, to constantly change, but Eva herself never really changes "sides". This makes it seem as if she is constantly betraying both sides.
 * Inverted: Eva is a loyal agent, but her agency keeps going over to the side of good... then evil... then good again.
 * Subverted: After joining the heroes, Eva appears to betray them... but is actually just pretending to rejoin The Empire so she can snag the MacGuffin.
 * Double Subverted: By its very nature, you can't double subvert this trope, as it's already a zig-zag(which is technically an extension of a double subversion) of Heel Face Turn/Face Heel Turn
 * Parodied: Eva just so happens to switch sides right before she gets her reward for following that side, and keeps making the same mistake every time she switches.
 * Deconstructed: The Empire has been helping Eva achieve her dreams, but she starts questioning their methods after meeting Alice and Bob and ends up joining their fight. However, her past makes it difficult for her to fit in with the other heroes, and she goes back to The Empire... but can't stand working for them knowing all they've done, so she rejoins the heroes. But now they trust her even less, and she doesn't have anywhere she fits in anymore.
 * Reconstructed: Or so she thinks. While Alice and Bob are still unwilling to trust her, Wide-Eyed Idealist Colin has been going to bat for Eva every time the discussion turns in that direction and has been very convincing in his defense, finally making Alice and Bob agree to give her at least one more chance. Accepted into the group once more, Eva finds a place she can do good and comes to settle in.
 * Zig Zagged:
 * Almost always is, between "Heel Face Turn" and "Face Heel Turn".
 * Alternately: Some seasons Eva keeps switching sides, others she stays on the same side the whole time.
 * Averted:
 * Eva never betrays them.
 * Eve is completely up front about having her own agenda, although not necessarily about what that agenda is. She's never on a side to begin with.
 * Eva switches sides and remains on that side for the rest of the series.
 * Enforced: "Eva isn't working out as a hero; let's have her go back to The Empire!" "...Wait, no, that isn't working..."
 * Lampshaded:
 * "Pick a side, Eva! I've had enough of this! If you want to stay with us, then come back inside and I will pretend this never happened, but if not...get lost. Go away and never come back!"
 * The secret base has a literal revolving door, marked "Eva."
 * When asked what side she's on, Eva has to check her watch.
 * Invoked: Eva is a double agent, and this is the most convincing way to get information on both sides.
 * Defied: Eva performs a Heel Face Turn or a Face Heel Turn. And that's it.
 * Played for laughs: Eva switches sides so often that it stops being treated seriously and just becomes ridiculous.
 * Discussed: "I still can't trust Eva. I just can't, there's no reason to. She doesn't even seem as though she's changed at all since she stabbed us in the back already, what's to say she won't do it again when things get tough?"
 * Conversed: "I've lost track: which side is Eva on this episode?"

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