Guide by Majesty (Discord: Majesty#8265)
Original Guide: https://forums.mihoyo.com/genshin/article/16153
I don't usually make guides for events, but due to the nature of the event not really explaining the items it gives you, combined with the fact that most people participating in the event haven't played the game before, I believe it is somewhat necessary to create this guide so people aren't straight lost doing it and ask the same question over and over again in all our different media platform. I'm going to attempt to keep all the complicated stuff out of the guide; if you want to understand how exact breakdowns work I highly encourage you to check the pinned guides in the official discord channel.
As you can read from the rules, the items are split into 5 different categories, each costing a different amount: A(10), B(6), C(4), D(3), and E(2). You can right now scratch off both D and E. Artifacts from D you will abandon basically an hour into playing the game, and items in E you can find in droves on the map and are meaningless. This leaves us with the A, B, and C categories. You are only allowed to bring items up to a total value of 16. Weapons in the C category are additionally marginally useful. If you read my beginner's guide, there are certain tradeoffs between using 3* vs. 4* weapons; however, those 3* weapons are relatively readily available in game through exploration. You'll be able to find 5 copies of them to make a max refine relatively early on in your journey. In addition, the only offensive weapon out of those is halberd, which is found in Liyue and thus has even larger quantities compared to the other 4 C weapons, which are all HP recovery utility weapons. As such, a C category weapon loses most of its effectiveness approximately 5 hours into gameplay, and is basically used as filler to max out your inventory weight.
As such, there's basically 2 loadout options you can do for the event, and the ones that are thrown out pretty much exclusively: 1A + 1B or 2B + 1C. Before I breakdown each of these options, I'll give you an overview of why items in these categories might be desired.
First off, if you haven't noticed for the items in category B, there's basically two flowers and two feathers. Regardless of which loadout you pick, your B item will always be a feather and not a flower. To understand more about artifacts, you may check the pinned guides, but the gist of what is important is that flowers give flat HP while feathers give flat Attack. That attack is way more valuable since it is an offensive stat compared to the HP from the flower. Flowers are actually normally upgraded last in the hierarchy, but in any case know that you will appreciate the attack from the feather much more than the HP from the flower.
Second off, you might be wondering what the difference between the two different colored feathers. Well, the red feather is almost unconditionally better than the blue feather. The red feather is part of a set called “Gladiator’s Longing,” the 2-piece effect giving 20% Base Atk and the 4-piece effect giving 40% increased damage to the basic attacks of any melee characters. The blue feather is part of a set called “Wanderer's Troupe,” the 2-piece effect giving 80 Elemental Mastery and the 4-piece effect giving 40% increased damage to the charged attacks of any ranged character. You can look up more about those stats in beginner's guide, but the gist of it is that elemental mastery is not a high scaling stat, and that 80 elemental mastery will only provide half the effect of 20% Base atk even on elemental based characters. Since you can only get 2 pieces of each set at maximum, the 2 set effects are what you're concerned about, so even for catalyst users who are pure elemental damage the 2 set effect of gladiator is almost always better.
Moving onto the A category items. The 4* claymore is a DPS weapon that inflicts additional damage every 15s and the 4* catalyst is a support weapon that regenerates energy to the user and hp to the party when the user casts their burst. Leaving the specifics aside, the important part is that they're relatively decent at their jobs as far as 4* weapons are concerned but not particularly amazing weapons. C category weapons aren't too important, since as I've noted you'll eventually get those in droves. You can pick one based on which character you'll use the most early on, but there's not much issue regardless of which one you do get.
Let's now discuss the advantages and disadvantages of both loadouts.
Starting with 2B + 1C, you'd most likely to running a gladiator feather + flower + 1 3* weapon. Why a feather + flower over two feathers?
Well, having two pieces of the set let's you concentrate power into one character early on due to set effects rather than spreading power out. Early on you really only want 1 character doing your damage, so concentration is better. That and you most likely won't have enough artifacts to upgrade 2 4* feathers, whereas you can just leave the flower unupgraded and still pull the 2-set effect.
A 4* feather is super powerful early on because of its difficulty or straight impossibility of acquisition otherwise as well as its comparative power. Before AR 35, world bosses will not drop 4* artifacts at all. World elites can drop select 4* artifacts starting at AR 30 but at impossibly low drop rates. If you've read my other guide you know that you will never run artifact domains below AR 45, so that's a no go. Some chests contain 1-time select 4* artifacts, but many of those sets are useless and you will not likely reliably have fished those out until at least AR 25, most likely AR 30+. Thus, for the first 30 AR levels and most likely until AR 35, you'll have a 4* feather you cannot get from other sources. A 4* feather gives you around 90 more attack than a 3* feather when both are maxed. This is absolutely massive early on and still will be around 10% of your total attack around AR 35. For comparison, the 4* claymore will not have 90 more attack that it's 3* counterpart until Ascension past level 70, which requires AR 40.
Additionally, having the 2 set effect available from gladiator makes your life much easier for getting your second 2 set effect. If you've read my beginner's guide, you would know that early on ideally you want a 2/2 berserker/sojourner since that gives the most unconditional base stats (15% crit/20% base atk) and is the most reliable to use. Having access to the 2 piece gladiator means that you don't have to fish for one of the two other sets. This is great since while you'll be rolling in berseker pieces, you won't get many sojourner pieces at all, so if you didn't have good luck you'll be able to save yourself from being forced to run 4-pc berserker, which has a good but conditional 25% crit at 70% or less hp, which is difficult to keep up consistently. Even better, if you roll good sojourner pieces you can run a 2/2 gladiator/sojourner, since base atk% is more effective than crit early on, and you'll be rolling anything you encounter.
On the other hand, once you hit AR 35 you'll start raking in 4* gladiator pieces. By the time you hit AR 45, you should have your pick of the litter for a 4* gladiator set, and you'll then have started looking into replacing your 4* gladiator pieces with 5*'s. As such, after this point you'll have likely replaced those set pieces and past AR 45 the two B artifacts will have lost almost all their use.
Moving onto the 1A + 1B setup, you'll still have access to a 4* feather so you'll have that additional 90 attack; however, you won't have the 2-set effect. You'll have access to a 4* weapon, but it will be unrefined which means it won't necessarily be better than a 3* weapon. You can read more about that in my beginner's guide, but higher refined, lower rarity weapons will normally be stronger early and comparable later to lower refined, higher rarity weapons. First let's consider prototype animus. Debate club, a 3* weapon, is the superior weapon for probably the first 70 levels compared to it at high refinement, so if you've rolled any gacha at all you'll have a replacement for it. Secondly, animus is in an awkward spot b/c the only claymore user you're guaranteed to get is Noelle, but Noelle prefers to use a crafted 4* called whiteblind which is a much better weapon for her than animus. Thankfully you can deposit these items anytime between 9/28 to 10/10 so you can wait to see what you pull before deciding, but you can run into the awkward position where you have a weapon and no users, so keep that in mind. On the other hand, prototype grudge is a straight support weapon. The 3* catalysts you'll find in exploration will always be better than it as an offensive weapon, so if you pick it it's only for support. It's not as bad as people make it out to be however. If you're keeping your catalyst users around just for their bursts, this item supplements that and it allows you to run high-uptime burst characters, you can use this weapon on them to replace a healer. Just don't expect to do any damage with it.
Concerning artifacts, your setup will be a lot more reliant on RNG compared to the 2B + 1C setup. You'll still have the 4* feather, but you won't be able to create a gladiator set effect until AR 35, when they start dropping from world bosses. That means you'll be making do with whatever berserker/sojourner pieces you get. Best case you can run a 2/2 berserker/sojourner, worst case you'll need a 4-set berserker. This means in the best case you'll have the worst case scenario as a 2B + 1C setup, and worst case you'll have something strictly worse.
The difference is that while the 4* artifacts are guaranteed to fall off later on, the 4* weapons are not. While between AR 35-44 the 4* artifacts will suffer some fall-off in usage effectiveness, the 4* weapons won't gain much usage effectiveness either, making it a wash in that range. On the other hand, the 4* weapons can still be used post AR 45, unlike the 4* artifacts. A R5 Animus can still be used as an offensive weapon, and at the very least can be used by a swap support to supplement damage at lvl 90. A Grudge will always be a good support weapon for its intended uses. Thus, post AR 45 the 4* weapons will still have use while the 4* artifacts will not.
Essentially, for all of early game the 2B + 1C loadout will be better, but for late game efficiency standards the 1A + 1B loadout will be better. Keep in mind that to reach AR 35, you'll probably take a month unless you sink in a huge amount of playtime to explore the entire world, in which case you could probably do it in 2-3 weeks. Either way, you'll have a big portion of playtime (50-100h probably) where you can have it much easier with the 2B + 1C loadout, as a tradeoff for it being almost useless post AR 45. Thus, as all other efficiency questions I have covered in my beginner's guide, it basically boils down to are you willing to suffer in your gameplay to get marginally better gains in the long run. Weigh these factors, then make your decision.
Pertinent information related to the factors I explained but not in detail can be found in the pinned beginner's guides in the official Discord server. All of my guides can be found on the forums if you go to my account and look for my posts if you're curious about my specific references, but don't be surprised if you're a complete beginner and don't get the topics since they're for more advanced information.