Why are Dialga and Palkia enemies?

Question

If you've seen in the games and anime, Dialga and Palkia are mortal enemies. They even had a fight that threatened to level a small town. What I don't understand is why. Why do they hate other so much? Tell me in the comments why you think they're always at each other's throats.

Comments

All I know is that they don't hate each other in the games.

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Not sure what you're basing that off of.  In main series, at least, they simply have no interactions.  We have no indication of whether or not they hate each other.

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In the Pokemon movies it's because Palkia thought that Dialga stepped on Palkia territory and in the games it's because they wanted to overthrow each other. Similar to Kyogre and Groudon.

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They never wanted to overthrow each other in the games. According to Cyrus, time and space depend on each other to shape the world and remain stable.

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It's Space versus Time... :/

Answer 1

Now, this isn't confirmed, but as far as I can tell, they aren't actually enemies.

The control two different dimensions; Space and Time, and are in a way opposites to each other. This is basically done with every single game where there are two legendary Pokemon that are two sides of one coin. This doesn't mean that they are enemies in any sense. One could argue that it's the whole "Space Vs Time" battle, but that doesn't really make sense, since they should live in harmony with each other.

Now for the movie, yes, the did fight. But there was also an explanation to why they fought two movies later;

Recently, Arceus has begun to awaken which has caused ripples in the space-time continuum. As a result, the Temporal and Spatial Worlds intersected with each other. Both Dialga and Palkia believed that the other had attempted to invade their territory which caused the battle that almost destroyed Alamos Town.

Source

This movie also explains the whole thing with Giratina, in case you were interested.