Guild Wars 2

With the latest lore we know that Dragon’s Energies can counter themselves and thus dragons can be harmful to eachother, especially when their Magic is opposite.

There’s a plan that we can make Jormag and Primordus fight with eachother what will end with killing them both at once, because Ice and Fire cannot be friends. Taimi told us that there’s not even a need of them being fully awaken and that active state is allright to make it done.

Why then the energy that was unleashed in the moment we killed Zhaitan didn’t kill or harm Mordremoth but instead made it absorb it.

I love Guild Wars 2 lore but kitten it’s getting too difficult for me and out of logic.

You’re assuming Mordremoth’s magic is diametrically opposed to that of Zhaitan, which we just do not know.
Don’t get me wrong, it could be true, but I’m just pointing at the fact that it’s only speculation. If Primordus and Jormag oppose each other and that Zhaitan opposes Mordremoth, then we automatically assume Kralkatorrik opposes Steve (DSD) which, in my opinion, really doesn’t fit.
Just my 2 cents