Compared to JoJo Brachydios, Gokukai Stygian Zinogre, and Dengeki Ivory Lagiacrus, this quest requires a bit more context. In short, this is a quest in Arena – a single area. There are 2 Green Plesioths in total: an insanely large one (as "Mama" afterwards) and a ridiculously small one (as "Chibi" afterwards). Notably, the quest does not require you to hunt both; managing to defeat just one of them results in a clear.
The armour piece crafted from this quest might offer a hint – instead of fighting bravely but brainlessly, play smart! Since the Chibi is not only small but has average health and damage, defeating it is not much of a challenge. This makes it debatable whether this quest belongs in the same category as the others mentioned previously.
Imagine some players saying they successfully solo cleared this quest, but only managed to hunt the Chibi? Of course, this still requires a smart strategy to avoid being noticed by the Mama. Once the Mama joins the fight, even if you do not really want to botther with her, she will faint you very quickly. In short, going alone without the Shakalakas and utilising Smoke Bombs properly is the best solution if the Chibi is your main target.
When playing in a smart way as mentioned before, I could finish this quest in 8:22 with Sword and Shield. Why this weapon? The key to this quest is avoiding detection by the Mama, so the ability to use items without sheathing your weapon is crucial. Sometimes being just a second late with a Smoke Bomb can ruin the entire plan.
Now, let's switch contexts and face the real challenge – the Mama. When targeting her, this is no longer a meme quest, but a seriously tough challenge. The Mama gets fatigued as usual, but she is incredibly bulky and lethal.
Given the lack of real attacking opportunities as well as the existence of the Chibi in a small area, many hunters overestimate her real health. Additionally, her insane size means you can hardly reach any weak spots with melee weapons, which significantly slows down your clear time. While a Heavy Bowgun build with Evasion +2 and Evade Extender can finish her surprisingly quickly, one hit from the Mama will likely faint you at the same time. It is a very risky and stressful plan that I would not recommend to any mortals at all.
Her damage multiplier is on a similar level to JoJo Brachydios, and her weird hitboxes only make things worse. When fighting against JoJo Brachydios, at least there are no distractions; here, you have the Chibi. And you usually know how and why you are hit against JoJo Brachydios; meanwhile with the Mama, you often faint without knowing the exact reason – she is a truly janky monster.
There is also a hidden design element here that some might already notice themselves: even if you avoid attacking the Chibi, it can eventually get killed by its Mama – the damage among monsters themselves is not negligible in MH3G – which is to me something I believe Capcom should keep forever. Depending on their relative positions, it becomes a race: can you finish the Mama before the Chibi dies? If the Chibi dies first, the quest ends (successfully, but not how you intended), and you only have 1 minute left to deal with the Mama, which is usually not enough time to end this challenge.
Because of the randomness of the hitboxes and the Chibi's interference, this quest is very inconsistent. Some hunters even consider it harder than JoJo Brachydios. However, while I have seen many people mastering JoJo Brachydios in different ways, I hardly see anyone having fun with this quest – usually one clear and farewell. Being difficult with a low clear rate does not necessarily make it a good challenge I guess?
Forget about the extreme builds for ranged weapons, I had to choose a safer or perhaps even the safest option. In the end, I decided to go with a defensive Gunlance build.
Weapon: Lucent Nargacuga Gunlance (七星銃槍「玉衝」)
Skills: Guard +2 / Guru Capture / Mind's Eye / Razor Sharp / Guard Up / Constitution -1
As one of the best Lucent Nargacuga weapons, this Gunlance has almost everything you need for damage output. Since the Mama is not exceptionally bulky, the combined damage should be enough. My focus, however, was strictly on the defensive side.
Guard +2 and Guard Up: Theoretically allow me to block every attack from both Green Plesioths. Agnaktor Z armour set also provides a decent Water resistance.
Razor Sharp: Reduces the need to use Whetstones frequently.
Mind's Eye: Prevents the accidental bouncing that could leave me vulnerable.
Capture Guru: To end the quest as soon as I can.
Even with such a crazily defensive build, the hunt did not go as smoothly as I had hoped. I failed the quest once because the Mama killed the Chibi first. I failed other times by fainting 3 times. How could that happen with a defensive Gunlance build? Well, sometimes the Chibi could cause unexpected trouble. More importantly, the weird hitboxes of the Mama are to blame – your brain tells you that you are going to block an attack properly, but the game tells you that you are wrong and boom! It is a quest with a poorly designed monster.
Even during the only time I managed to solo clear it by myself – capturing the Mama in 39:29 (though I failed to kill the Chibi afterwards) – I still fainted twice, and I did not even have Fortify in my build! That successful attempt felt more like a relief from heavy stress than a great achievement. This is the key reason why so few hunters enjoy grinding this quest compared to JoJo Brachydios – hard ≠ good.