In MH3G, there are only 3 quests of Alatreon in total – 2 of High Rank in Village and Hub and only 1 of G Rank in Hub as a download quest. As a download quest in G Rank featuring such a god-tier monster, you should already expect it is going to be tough. However, the rewards of the quest are worth the challenge, as parts of Alatreon allow you to craft many of the best Dragon weapons in MH3G.
Since you can wear G Rank builds for High Rank quests, the corresponding 2 there are very manageable. They might still take you some time to struggle depending on your weapon and game plan, but clearing them should be fine. The G Rank one, however, remains a massive challenge for solo hunters. Fortunately, the legendary Slingshot turns out to be very effective against Alatreon. Building around the Slingshot offers relatively good agility and survivability, a clear game plan, and even the possibility of fully break the horns.
As a crazy fan of farming sets, my initial plan was using Golden Rune armour set. However, given a ridiculously low Thunder resistance of the set, even a High Rank Alatreon could almost faint me in a single Thunder attack! Among its colourful elemental moves, the Thunder ones are the hardest to dodge consistently with the Slingshot for me back then. Though very reluctantly, I had to move on from Golden Rune armour set.
In the end, I picked Gigginox X armour set to replace Golden Rune. That meant no more farming skills and fewer rewards, but at least I would be more likely to survive.
While Gigginox X armour set can withstand Thunder attacks, this time a single fireball will cause a faint – so I had to be extremely careful with my positioning. Fortunately, fireballs are way easier to avoid.
Gigginox X armour set comes with Capacity Up and Status Attack +2, making it possible to trigger Paralysis and Sleep 3 times each with all the necessary combination items, which almost guarantees breaking the horns when done properly.
Gigginox X armour set also offers Evasion +1/+2, which will greatly help boost the fragile hunter in a ranged build with guaranteed elemental weaknesses.
With a fully optimised build and a backpack full of items, I eventually cleared the G Rank Alatreon by myself. It took around 30 minutes with one faint, and I broke both horns. Since I did not need any more parts from Alatreon back then, I left it at that.
I already managed to solo clear the G Rank Alatreon with Bow back in 2015. Honestly and more specifically, with the legendary Slingshot. I went with a very complex game plan, which turned out to work as expected to fully break the horns. Meanwhile, that is still a long and stressful quest to play.
In 2024, with more knowledge of its movements as well as the whole series, I switched back to my favourite Golden Rune armour set. Those Thunder attacks still fainted me in one hit, but it should be fine as long as that did not happen – though occasionally they still did!
Without Capacity Up and Status Attack +2, I could only trigger Paralysis and Sleep twice each. This makes breaking the horns less stable, but the farming skill of Great Luck is simply too seductive to leave out! If you are not targeting the horns, you can ignore the status coatings and just keep shooting from the beginning: this can shorten the average clear time by at least 5 minutes! However, since one of its rarest parts does come from the horns, you usually have to go for them while sacrificing the efficiency to some extent.
Of course, the legendary Slingshot is not a must against the G Rank Alatreon. I have cleared the quest with a few melee weapons as well, but with an average time of 40 minutes each.
Sword and Shield: This has a terrible matchup against Alatreon. You can almost never reach the horns, and it is not actually that safe. The low damage output even caused me to fail once because I ran out of time, something that rarely happened, even with those famously insane download quests. I learned the lesson, played more aggressively the second time, and eventually cleared it, but fainted twice during the run. I would not recommend this weapon against Alatreon at all, except perhaps in a supportive role for a team.
Long Sword: Surprisingly, this was not that bad. The long reach allows you to hit the horns, though it still is not quite enough to fully break the horns in a consistent sense. In the end, I managed to clear and survive without even fainting even for once – phew!
Gunlance: I know that Lance and Gunlance will always shine against most of the crazy and evil monsters since the beginning. Given the Gunlance's upward poking motion, you can reach the horns just as well as Long Sword. Of course, it will still be much slower than the legendary Slingshot – you just cannot beat the official cheat – Gunlance turned out to be very safe, as expected; and even faster than Long Sword, which was unexpected.
Ultimately, these melee runs were all for fun! For farming parts or higher efficiency, you already know which build to use!
To farm horns, you usually have to neutralise Alatreon as expected: MH3G is a game in an era without subquests. And while the quest rewards can theoretically offer any parts of Alatreon, the rate of horns is unbelievably low – do fully break the horns manually and properly – by Capcom. Interestingly, when utilising the legendary Slingshot, the Dragonsphire often becomes a bigger bottleneck than the horns.
To deal with that, I found a genius build online that inspired me. The strategy revolves around 2 key mechanics below:
Sleep Damage: The first hit on a sleeping monster will deal 3x damage;
Cannon Mask: The Shakalaka Cannon Mask can actually sever a tail! Beyond that, in a single shot when done properly.
That said, here comes the inspirational build:
Carving Master: To get 3 carves from Alatreon’s tail instead of 2.
Shakalaka Rally: To increase the canoon damage so it can cut the tail in one hit.
Rock Steady: To nullify Alatreon's initial roar, allowing to shoot Sleep Ammos immediately.
Speed Gatherer: To shorten the time required for those 3 carves.
What a brilliant idea! This build alone increases grinding efficiency to a new level and is incredibly fun to play. Key steps are elaborated below:
Put Alatreon to sleep;
Launch the cannon with the Shakalakas;
Carve the tail for 3 times;
Faint yourself if a Dragonsphire spawns or abandon if not, to end the quest.