|Objective: Hunt all target monsters|
|Reward Money: 7920z|
|Time Limit: 50 min.|
|Conditions: HR 9 or higher|
|Failure Conditions: Time Expires / Faint 3 Times|
|Other Monsters: Aptonoth / Jagras / Mernos|
This quest's difficulty is highly a matter of chance, as if you end up with both the Rathalos and Rathian attacking you at the same time, things could get tricky... unless you know how to use them to your advantage. This pairing of monsters - unlike the pair of Tzitzi-Ya-Kus you may have fought earlier - are much less pacific, and share the same habitat (both will frequently roam about AREAS 14, 15 and 16). Simply put, there's a good chance you'll actually end up facing both of them, so you'll need to be prepared for this likelihood.
First, you'd be wise to tool your armor to the occasion. The Fire Resistance and Poison Resistance skills will serve you well, as the Rathian and Rathalos both will rely on fire breath and poison tail attacks. Bringing along buffing items like Demondrug and Armorskins is also ideal, and since both foes fly, having a healthy supply of Flash Pods prepared ahead of time will serve you well. You can only carry three at a time, of course, but there's nothing preventing you from returning to a camp mid-mission and restocking.
If you wish to avoid fighting both as much as possible, consider also creating some Dung Pods, which can be loaded into your Slinger and fired at the offending monster. This will, with any luck, drive the beast away, as it turns out that monsters don't like being pelted with poo. This won't keep the monster away forever, and it may take more than one Dung Pod to drive it off, but it'll at least force it to vacate the area and give you time to focus on whichever monster you didn't drive off. Also be sure to bring traps and Tranq Bombs, as when one of the monsters is near death (search for tracks ahead of time to build up your Scoutfly Level so you can see the skull indicating its near-death status) you can save yourself a great deal of trouble by letting it flee, then capturing it in its lair. No sense in having to do all the work of hacking the monster to death if you can take a short cut, especially not when there's another monster waiting.
Alternatively, if you're confident in your abilities and have a weapon that allows for quick attacks and dodging, you can engage both at the same time. The Rathian and Rathalos aren't fun foes to face at the same time, as they're relatively large and their attacks can cover a good area. Not only that, but their attacks are diverse, as they have melee, charge attacks (both on the ground and aerial) and ranged, breath weapon attacks. That said, their attacks do not discriminate against each other, their aerial tail flips being especially likely to hit each other. Keep the Rathian between you and the Rathalos, dodge their attacks and take the odd opportunistic strike of your own. This is obviously a riskier approach, as there's a lot that can go wrong - one roaring at the wrong time may allow the other to score a decisive, uncontested hit, but generally it works out better than it may initially seem, provided you have enough room to dodge and have a full stamina bar.
However you go about it, once you complete this quest return to Astera and talk to the Armory clerk in the Workshop to obtain the Bandit Mantle. This hunter tool, when worn, will cause enemies to occasionally drop items in addition to the materials they usually drop. The main purpose of these items is to simply sell them for Zenny, and the value of the item dropped depends on the power of the monster attacked.