Ask Haku all of the things.

[Elija2]

Why do you want to finish Ada's campaign before playing Mercenaries?

[Hakudamashi]

Because I want to play the game by myself.

[Elija2]

So you're saying that you're never gonna play Mercenaries with me ever?

[Hakudamashi]

I'm not saying that at all.

[Elija2]

Because I want to play the game by myself.

Why would playing Mercenaries with me get in the way of you playing by yourself? You can still play by yourself afterwards (but it's not like you were planning on playing the Ada campaign anytime soon).

[Hakudamashi]

It has everything to do with fatigue.

[Elija2]

What do you mean?

[Hakudamashi]

Essentially, unless it's a fighting game, fatigue is gonna catch me.

[Elija2]

So you're saying that you don't wanna play the game for a while?

[Hakudamashi]

Yes., that is what I'm saying.

[Elija2]

But when you do return to it, why won't you want to play Mercenaries before Ada's campaign?

[Hakudamashi]

Because I wanna see how the story ends.

[Elija2]

You can't do that after playing Mercenaries?

[Hakudamashi]

I can.

[Elija2]

Then why don't you?