User blog comment:Redfork2000/Top 10 Rivalries in IaLR/@comment-30384301-20180415003922

Great list! Here are some rivalries you might consider:

Takeshi vs. Akasha 

Both are siblings, and Akasha is older than Takeshi. In Takeshi's debut story, The Shock about the New Shadow, Takeshi follows Akasha's orders to kidnap Kyoji and many more, until the last straw came when Akasha finally orders him to kill Kyoji. Takeshi turns against Akasha, but not long before he gets roasted literally. Kyoji resurrects him in exchange of the destruction of the Elementia, Kyoji's sword, and in return, Takeshi joins Kyoji to fight Akasha. Akasha might possibly be holding a grudge against Takeshi, so that leads to a possible rivalry.

Sasuke vs. Scorch

They have similar personalities. They are crazy in battle, hoping that they will be able to win against their opponents and have their favorite words as well.

Sasuke: WATER!

Scorch: FIRE!

They don't have much interactions but this rivalry might become interesting when they do meet. After all, one of them is a hero and the other is a villain.

Starcade vs. Electra

Both are girls. Both are intelligent and are experts at computers. Both are complimented to be beautiful-looking by different sides. Lastly, both Starcade and Electra are determined to destroy each other in the worst ways possible.

Emma Emerald vs. Sean Sapphire

Emma is a forest queen and Sean is a pirate captain. With their different personalities and high ranks, they might have a possible rivalry between each other.

Re-Peat Moss vs. Re-Peat Boss

Simple, they hate each other. Re-Peat Moss calls his evil counterpart a "TRICKY carbon-copy of himself" and the like. Re-Peat Boss on the other hand simply views his good counterpart as a nuisance, a pest in the way of his desires to crush the Locked Room Gang.

Green Shadow vs. Galaximus

Green Shadow is a good pea, while Galaximus is an evil inkling. And since peas are naturally rivals with inklings, Green Shadow and Galaximus are no exception.

Test Subject Blue vs. Hot Air

Similar to Captain Red Shell vs. Black Gem, except that Test Subject Blue is Captain Red Shell in this case, while Hot Air is Black Gem.

Green Shadow vs. Dark Green Shadow

Even though Dark Green Shadow doesn't appear as much as Green Shadow, she nonetheless hates her good counterpart, or as she calls "good me". In An Unpeasant Surprise, she was created by Akasha and sent by her to pretend to be Green Shadow and sabotage the gang's weapons, when Green Shadow herself was frozen in a freezing tank. In Evil Counterpart Saga, Dark Green Shadow returns to take down her good counterpart, and when she fails, she calls upon other evil counterparts to assist her. This shows how bitter the rivalry between the good and evil Green Shadow is.