Rewards in the break/capture part of the reward screen can overlap. If you capture a monster you get 2 capture rewards, minimum. I don't know if there is the possibility of getting more even without Tranquilizer skill. However, if you capture two monsters, you might only get 3 capture reward, beause one of them overlapped. This is relatively random. Break rewards is the same. If you do a quest with a Diablos and a Black Diablos, you might only get one break reward even if you break the horns on both of them.
I would like to see proof of this, because it surely didn't work like that in MH3, and I don't see the point of penalizing the player by only giving 1 break reward if he breaks both Diablos and Black Diablos' horns. Are you sure you just didn't miscount break+cap rewards?
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i cant really offer proof without a way to record my gameplay, which i dont have. so you can choose to ignore my claim if you want to, but that is how it works, and also how it worked in Tri, which is where i first discovered it. --- "Lupus! Is it lupus?" -George Costanza "It's never lupus." -Dr. Gregory House
To be more specific, break rewards can overlap only if you hunt more than one of the SAME monster (subspecies included). You can't get overlapped rewards by breaking wings on Rathalos and Rathian on the same quest, as my recollection goes. But you can by breaking the wings on two Rathian or a Rathian and a Pink Rathian on the same quest. --- "Lupus! Is it lupus?" -George Costanza "It's never lupus." -Dr. Gregory House