In 2021, I did a special run with MH3G on Citra with Gunlance and key quests. The rule in short was that, I could only take key quests (both village and hub) with Gunlance. Overall it was a worthwhile experience to learn this relatively complicated but interesting weapon.
Restricting to only one weapon like Gunlance or Hammer is simple to understand, like many hunters only know how to use one of the available weapons. The other restriction – only key quests – is something different. Instead of directly making the hunting experience more difficult, the restriction is more likely to affect the available builds, which will require more time and effort with research.
For example, even if a monster is available in this run, as it spawns in one of the key quests, it does not assure that I can build its weapon or its whole armour set. Because the corresponding parts may require drops from other monsters that are not included in any key quests, that means no access to those monsters, to those drops, and hence to the parts.
For the village part, my final goal was clearing 「双界の覇者」. Of course there are more graduation quests afterwards, but these will not spawn by taking only key quests, which means out of my consideration.
The builds I used during the run:
Low Rank: Barroth Armour Set and Barroth Gunlance.
High Rank: Barroth S Armour Set, Barroth Gunlance and Brachydios Gunlance.
G Rank: Steel Uragaan Z Armour Set, Barroth Gunlance and Brachydios Gunlance.
Both Lance and Gunlance are incorporated with heavy shields to block attacks. These shields are almost useless against weaker or minor monsters, and only make the fights longer. However, the shields do shine a lot against stronger monsters and can be very useful sometimes – like those underwater fights – but requiring skills Guard +1/+2/Up. That said, I would better consider armour sets that already have those skills. In both Low Rank and High Rank, I chose Barroth armour sets – Guard +1 for Low Rank and Guard +2 for High Rank.
Since Brachydios is the main monster on the cover case with its iconic Blast as the new ailment, Brachydios Gunlance is one of the best in MH3G. Additionally, simply grinding the key quests of Brachydios is almost enough to build the weapon – there was no reason of ignoring that in my run. But since Brachydios does not spawn until the middle part of both High Rank and G rank, I used Barroth Gunlance to handle the transition period.
For G Rank, I chose Uragaan Z armour set, as it comes with many useful skills for Gunlance including Guard +1, Artillery Expert, and Mind's Eye. The usually useless skill called Bio Master proved to be effective against Brachydios, and the only negative skill namely Doggy Paddler only causes trouble for underwater quests – there are not many and the negative skill can be easily corrected. There was a final reason of using Uragaan Z armour set, its high Fire Resistance of 20 would help a lot against the final BOSS Dire Miralis.
Once I completed Uragaan Z armour set and levelled up Brachydios Gunlance to its highest form, the run was pretty much over – more than enough to beat almost all normal quests – including the final BOSS Dire Miralis in the hub with an insanely long quest name called 「黒焔盛んにして災異未だ止まず」.
Of course some players do hate the crap, but overall Dire Miralis is a decently designed final BOSS in MH3G – a huge and bulky monster that can fight underwater – one of the iconic but controversial systems in MH3G. Not a cheap monster at all, especially when you first fight against it with a relatively low defense.
Its underwater movements and hitboxes are pretty janky, which can be annoying and lethal for weapons that cannot block.
Its famou magma blocks can cause ridiculously high damage if your build has a low Fire Resistance, and their randomness only makes things much worse.
With similar reasons, Dire Miralis in the download quest with even higher health and damage turns out to be surprisingly scary for most weapons.
But in my run, I was using Gunlance with Uragaan Z armour set:
When things did not go as what I expected, I could block to survive!
With a high Fire Resistance of 20, the random and annoying magma blocks were no longer that scary or lethal.
With enough preparation beforehands, I cleared the final quest in one go – though I still fainted once. That was the end of the run, which took me around 73 hours. Considering that G Rank exists in MH3G and there are more key quests to clear, the time required is reasonably a bit longer. It was a great opportunity to learn Gunlance thoroughly in this sepcial way, and after the run, finally I learned to play Gunlance properly.
Given its low agility, of course, there were many tough or more precisely unpleasant fights when using Gunlance. Meanwhile, there did exist some extremely effective ones that I never expected so. That said, Gunlance is an interesting weapon with some unique features, and could shine well in specific scenarios. However, it is nowhere near an all-rounder weapon or one that suits the modern environment with a much faster pace. In short, if you want to either stick to one weapon or play fast, please avoid Gunlance and consider another weapon.