[Chaos Zero] Character Development Priority for Half-Anniversary Players

One way or another, 'Chaos Zero Nightmare' has been released for half a year now. First of all, congratulations!!! It's truly a joyous occasion.

Looking back, I've said plenty of things like 'This is unacceptable as a deck-building roguelike,' and while I still hold mostly the same opinion, thanks to improvements and content additions, I've ended up playing it for half a year regardless.It's a game that's fun overall despite my complaints.

This article focuses on characters to prioritize for development, which is likely the biggest concern for new users who have increased slightly due to the half-anniversary. You'll likely struggle with a lack of development resources early on. So, I thought I'd write this. For your reference.

To state it beforehand, absolute beginners should look at this page instead. If you want to gather information comprehensively, from supporters and Ark City to development elements and daily tasks, that's the place to go.

Updated 2026/04/29
Since there was various information updated during the official broadcast, I have revised and updated the recommended characters accordingly.

How to decide development priority

Let's decide on a main attacker

It's the fate of almost every social game, but firepower is justice. Offense is the best defense.

So, please choose one main attacker. Pour your development resources into them. This is the best practice.

However, the troublesome thing about this game is that you can't tell at a glance who can be a main attacker. There are characters whose operation changes significantly depending on the build, characters whose opinions are divided even among users, and there is no clear distinction within the game.

Therefore, this time, based on my own judgment and the general atmosphere of the community, I will introduce 11 5-star characters who can be candidates for main attackers. You could pick 4-stars, but everyone wants to use 5-star attackers anyway, right? In reality, 5-star attackers are basically stronger than 4-stars.

So, first, let's choose from these 11 characters and start developing them!

11 main attacker candidates. The reason I'm using collapse images is because this is the only icon officially distributed by the management. Although it's just a cutout rather than an icon. They won't distribute normal icons. Sorry if you're worried about spoilers.

By the way, what half-anniversary players are probably wondering about right now is,the classic gacha-game question: "Who's actually strong?"—but as someone who loves deck-building roguelikes, I want to say, "There's no such thing as strong or weak characters."

I want to say that, but...!

Since this is a gacha game, I can't avoid expressing my personal opinion...! Honestly, there are some characters you should avoid...!

So, for all you lost lambs out there. No, this isn't a strength tier list! It's strictly a"recommended development" order with Season 3 in mind!!!!

In all seriousness, character strength in this game (based on the current environment) changes drastically depending on the season, content, and virtual opponents. I have a feeling the evaluations for Nine, Rita, Meilin, Yuki, and Chiron might shift in Season 3. Some characters' evaluations will likely change significantly due to ability adjustments in updates as well.

I don't have Luke, so I don't know. My gut feeling puts him around B to A.

If we're talking about Season 3, Diana is overwhelmingly the top priority for main attacker development. She's been featured in recent pickups, so I imagine many people have her anyway. Please feel free to invest in her with confidence.

Since the environment in Chaos Zero changes significantly every season, the meta characters change accordingly.Basically, the new characters introduced in each season are almost without exception top-tier meta,and based on past trends, Diana should remain at the cutting edge of the meta until around mid-to-late June.

Looking a bit further ahead, thelimited character Heidemarie, who appears after the 2026/04/29 half-anniversary update (Season 3), will be a serious top-tier meta pick.It's clear from the official broadcast that Diana is designed with synergy with Heidemarie in mind, so in that sense, investing resources into Diana now is a sound decision.

If Diana and Heidemarie turn out to be duds in Season 3, please go complain to Smilegate. Not me. There is the precedent of Yuki, after all...

Part 2 for the lost lambs. After looking at about 8 sites, this was the tier list that best matched my own intuition as of 2026/04/23. For those who want to get a feel for things, including 4-star characters, sub-attackers, and supports.

Priority for Mika, Rei, Nia, and Cassius

Regarding Mika, Rei, Nia, and Cassius.No matter who you ask, they will tell you, "You absolutely must raise them."I agree.

4-star supports remain active from the early release period all the way to the half-anniversary, and it is not at all rare for them to be included in ideal team compositions over 5-star supporters.

• Multiple teams are required for endgame content

• Unlike main attackers, they are less susceptible to meta shifts

• High aptitude as a companion for Chaos farming = gear optimization

• Since they aren't pure attackers, you don't need to max out their development

For reasons like these, they offer great value and long-term utility. I wouldn't say you need everyone, but you should definitely develop at least two characters.

…Enough talk, just tell me who I should develop!!!

With that said, I have prepared a quick reference guide based on my own judgment. Please choose your preferred 4-star support based on the main attacker you want to use.

The concept behind this quick reference guide is to list the top two characters I would recommend when asked, '(I want to use this main attacker,) which 4-star support should I develop?'If you're still unsure, I recommend the two characters Mika and Nia. AP gain and draw sources are almost never useless.

No, I understand, please calm down, experts. I know what you want to say: 'Are you serious about removing Rei from Diana's list?', 'Cassius has a wider range in high-difficulty content, right?', 'Everything changes based on builds and specific enemies, right?', 'You don't even have Luke, do you?'. I understand. I understand, but, well, well, well.

Mika's strengths are her high healing amount and AP gain. At present, there is no team composition where AP gain is completely wasted, with the exception of Chizuru. I especially recommend her to beginners aiming for stable Chaos farming.Don't underestimate her just because she's an initial freebie. On the other hand, her draw capability is extremely weak, and depending on the team, she might just let AP go to waste. Since she doesn't contribute to firepower, she tends to get left out in score attack modes.

Nia is a powerful draw source. She has great synergy with main attackers who spam 0-cost cards, and since she can actively trigger 'Discard,' she also has high synergy with certain characters and shared cards. If you're struggling in high-difficulty content or score attacks, go with Nia.Personally, I think she has the highest overall rating among 4-star supports. However, the difficulty of optimizing her gear might be a bit... high.

Cassius is a bit tricky. He is a character who generates special cards when you use cards in combinations like cost 000, 111, or 012, and then uses those to fight.He has particularly high aptitude for high-difficulty content and score attacks, and even after being reworked, he is enjoying a second life. Since it's usually a prerequisite to build the team around him, he is for advanced players. The frequency of gear optimization also tends to be high.

Rei is a firepower buffer. While firepower buffs aren't universal due to target issues, she has many cards in the enhancement category that are removed from the deck upon use, and she also has cards that 'vanish' cards,so it's nice that you can also perform deck thinning at the same time. However, firepower buffs are common among 5-star supporters, and depending on your roster, the fact that she might end up on the bench more often can be considered a major drawback in terms of development priority.

Well, I think you'll end up using everyone somewhere, so ultimately I think it's fine to choose based on appearance. Deciding who your main attacker will be is more important.

Unfortunately, 5-stars that should be developed later

I hate to say this, but unfortunately, there are 5-star characters that should not be prioritized for development. Specifically, these are the 5-star support characters. To name them, Magna, Tipera, Calipe, Orlea, and Nadja are not priorities. Some people might get angry, but I'm stating it clearly.

I repeat, this isn't about character strength, but strictly about development priority. In fact, Tipera and Orlea were top-tier meta in Season 2, Nadja had bad timing for her release so practical applications weren't really discovered, and Magna and Calipe are good at guarding. Yeah. Maybe they are actually mediocre. No, the environment is bad. The content is bad.

Setting aside performance-based arguments,5-star supporters are specialized units, and their effectiveness tends to be heavily influenced by team composition and the specific enemies faced.Therefore, it is difficult to lightly recommend them to newcomers who lack development resources. Assuming the Season 3 environment, though this is just a guess, the value of Tipera and Orlea will likely drop.

In the first place, as mentioned earlier, 4-star supporters in Chaos Zero are excellent enough to fit into optimal teams and are more versatile.Because you are in the early stages where you are struggling with development resources, you should prioritize characters that can be used universally in many situations. That is what I think.

Of course, if I were giving one-on-one, specific advice, this wouldn't necessarily apply. If someone asks, 'I pulled Nine and want to use her, who has good synergy?', it wouldn't be wrong to recommend developing a 5-star supporter like Tipera or Orlea.

So, while I say you can put off their development, I'm sure you have the desire to try out various team compositions, andtrying out various compositions is actually the most fun part of a deck-building roguelike, so ultimately, I think you can develop whoever you like.

Besides, it's boring to keep using the same characters regardless of their strength. The most that happens if you develop weird characters is that you might not be able to clear high-difficulty content or get all the score attack rewards. Being 'fun' is important. Much more so than immediate rewards.

Who should you choose for your 5-star selection?

The 5-star character selection ticket that will likely be distributed during the half-anniversary.The targets are limited to characters that were implemented at the time of release.

I'm asking who I should choose!

I will tell you. The 卍Truth卍.

Updated 2026/04/28

Surprisingly,all characters implemented by 3/18, excluding Seleniel, are now eligible for exchange. You can choose anyone except Diana and Seleniel. Are you sure about this!?

Honestly, Veronica is the only choice.

There's no room for debate. It's Veronica, no matter how you look at it. It's divine providence. You could even call her the perfect form of a sub-attacker.Once you pay just 1 cost on the first turn, you can just leave her there and she'll function in any situation. She's a hidden broken character who can shine in Chaos, high-difficulty content, and score attacks. Always a 90/100. She even got buffed, for crying out loud. She's been given the green light.

She deals 2,000–3,000 damage per turn with 0 card usage, has abundant draw sources, can compress your deck, and on top of that, the difficulty of optimizing her isn't even that high. Unless you don't have a main attacker, if you already have your core main decided, it absolutely has to be Veronica. Especially since she's likely to remain relevant the longest.

Similar to the logic behind why 4-star support training priority is high, the biggest point is that Veronica is hard to be affected by the meta. In fact, Veronica always showed up in high-difficulty content and score attacks during the early release and Seasons 1 and 2. Why is that? Because the foundation of a Chaos Zero team is a meta-main attacker + sub-support or support-support.Veronica has managed to stay in that support slot perfectly. That's all there is to it. But that's what's important.Especially from a cost-performance perspective.

Actually, I don't think there's any main attacker that has bad synergy with Veronica. Maybe only if they interfere with the 'Fragile' (a debuff that increases damage taken by 1.5x) effect.

I won't go into specific details, but as long as the 1st and 3rd 'Breather' inspirations aren't nerfed, I think Veronica will continue to reign as a top-tier character. Even if her position as a sub-attacker were threatened, her versatility as a draw source is just too high. It's also nice that she has a 'hardcore' look, which is rare in Chaos Zero.

But what if I already have Veronica!?

If you're asking for a recommendation for someone who says, 'But I already have Veronica!!??!?', then it's Hugo.

Hugo is a so-called follow-up type sub-attacker. I wonder if terms like 'link' or 'chase' make sense to you. He automatically performs additional attacks in conjunction with an ally's attack card, and just like Veronica,once you pay the opening cost, he'll rack up follow-up damage on his own. It's also worth noting that depending on his inspirations, he can become a rich source of card draws.

What's different from Veronica is the narrow selection of main attackers he has good synergy with. He can't show his true strength unless you pair him with a character who uses a large number of cards. Conversely, if he fits, he becomes a better optimal solution than Veronica. The top contenders are Meilin-Luke, 4-star Tresa-Cassius, and he has decent synergy with Chizuru too. His synergy with Diana isn't bad either.

Personally, I don't rate Hugo that highly, but he's still strong enough that if I had to choose from the initial 5-stars, I'd pick him. The sub-attacker position is just that strong. By the way, you rarely see Veronica and Hugo used together. You'd want to include a supporter, after all.

How about Meilin?

SHE'S GOOD.

She's good, butif you have Diana, you don't need to go out of your way to choose her. That's what I think.

Meilin is a main attacker with excellent hit count. Since she can apply "Passion Weakness," she can be used while ignoring attributes to some extent. Her strengths are her high firepower, moderate difficulty in optimization, and decent Chaos aptitude, allowing her to be active in a wide range of areas.

You might think she was countered by the "Elasticity" gimmick, but she adapted by changing her build and is doing just fine. She struggled in environments that required high single-hit damage like Season 2, but there is no doubt that she stands a head above the rest as an initial 5-star main attacker.

However, if you have Diana, you can skip Meilin. They share several similarities: both are Passion attackers, both gain firepower through hit count, and both have many 0-cost cards. Furthermore, since Diana will likely be top-tier in Season 3, if you ask me whether you should go out of your way to choose and build Meilin, who has similar characteristics, I'd say... wouldn't it be better to just prioritize Veronica or Hugo?

Conversely, if you haven't built Diana for religious reasons or otherwise, I highly recommend Meilin. Meilin herself is quite strong. Just to be clear.

I heard Nine is the strongest, is that true?

When gathering information, you might see reviews saying Nine is an overpowered character that breaks the game. I generally agree, but please don't forget that most of Nine's evaluation is based on the Season 2 environment.

I hate to be repetitive, but character evaluations in Chaos Zero change significantly every season, so there is no guarantee that Nine will be able to perform just as well in Season 3. In fact, I'm a skeptic, so I suspect that the fact that her targets have expanded might hide the background assumption that "she won't be that broken in Season 3, so it's fine to give her away."

BUT!!!

Even if there is a theory that she might be mediocre in Season 3, I personally think Nine is worth choosing. She is stable in Chaos, easy to operate, super easy to optimize, and has an incredibly wide range of builds and team compositions. Furthermore, Nine can be differentiated as a main attacker with high single-hit damage, which is the exact opposite of hit-count-based attackers like Diana and Haidemarie.

If Veronica and Hugo are sub-attackers/supporters with many job opportunities, Nine can be called a main attacker as a job opportunity. Depending on the build, she can carry almost any sub-attacker/supporter. As long as high hit counts aren't required, she has the power to respond flexibly in a wide range of content. If I were threatened to pick only one strongest character regardless of the season, I would choose Nine. She is broken.

Well, if you want to use Diana or Haidemarie effectively, I think choosing Veronica or Hugo is fine. If you want a third attacker who has both strength and versatility, I think Nine is a good choice. Since Chaos Zero requires up to three teams, a third attacker is important in that sense as well.

Brief commentary on other initial 5-stars

Basically, I don't recommend it, but you can choose characters based on your personal preferences. So, here is a brief commentary.

Rita (Main Attacker)
My personal top recommendation. She is simply strong and the most fun to use. While she is similar to Nine in the category of high-cost attackers, the feel of playing her is quite different. Her basic strategy involves gaining her own unique AP-like resource to effectively bypass costs, allowing you to spam 2, 3, and 4-cost attack cards. Surprisingly, she also has a wide range of build options. Managing her unique buffs is interesting, so I recommend her even setting aside her raw power.

Haru (Main Attacker)
. A Rita who traded cost-bypassing for increased firepower. She is a slow starter whose performance depends entirely on how many times you can spam her 2-cost "Anchor Shoot," which increases in multiplier each time it is used. Many people underestimate her, but after two buffs, her slow start can be mitigated by AP generation methods like Mika or Tipera. Her 2-dupe bonus is quite broken, so if you have her at 2 dupes, you can definitely prioritize building her.

Lin (Main Attacker)
. It is important to maintain her unique buff called "Black Cloud Stance." Since the stance only breaks when you use another character's attack card, it is easy to manage by adjusting the order of cards played or your team composition. Her firepower is second only to Meilin among initial 5-stars, and I feel she is top-tier for the Void attribute. For better or worse, she is easy to use because there isn't (probably) a single optimal team composition for her.

Chizuru (Main Attacker)
. A quirky character who gains a cost-reduction buff in exchange for being unable to recover AP in principle. Once you reach end-game optimization, the downsides start to outweigh the benefits, so my impression is that she might be a bit tough in the long run. She is an attacker who can rack up hit counts and her firepower isn't bad; there are also buffs and mechanics related to hit counts, so she could shine if the environment aligns with her.

Chiron (Main Attacker)
. An AoE attacker. Strong in long battles, but bad in short ones. Since the only environment where AoE attacks are useful is Chaos, she is currently struggling. The environment is against her. It is an interesting point that she can also heal. While it is a bit lacking in fun that she doesn't have much build variety, she could suddenly become very strong if an environment arrives that utilizes her concepts of "Annihilation," "Status Ailment Cards," and "AoE Attacks." She is one of the rare male characters.

Lenore (Main/Sub Attacker)
. A character with an interesting mechanic where she generates "Requiem Bullets" that trigger additional attacks when moved to the discard pile. I want to utilize this, but if you leave the bullets unused for too long, your deck gets clogged. So, she is strong even if you use her casually in battles lasting 3 to 6 turns, but in long battles, you must have a way to process the bullets. She is easy to use because she has good synergy with 4-star supporters like Mia, Ray, and Nia. She also has synergy with Diana regarding "Bullet" cards, so she is a viable option.

Orlea/Tipera (Supporter)
. If you want to use characters that require high-cost single-hit firepower like Nine, Haru, or Rita, you can prioritize them. Conversely, they don't have good synergy with characters that rely on many small hits. They are truly specialized supporters. It is difficult to say which is stronger, Orlea or Tipera. Orlea's key is "Preservation," while Tipera's is "Number of Cards Used," so their usage feels are polar opposites. You can use both together to support Nine or Haru, so they don't conflict. Ultimately, you can even choose based on appearance.

Nadja (Supporter?)
. A quite unique supporter. She can be used in multiple ways, such as a special healer who can recover when attacks hit, a pure firepower buffer, or a defense-dependent attacker. Perhaps the evaluation of "all-rounder" or "jack-of-all-trades, master of none" is the most accurate. It feels quite tricky to introduce her as a recommended character. She earned a non-practical reputation as the strongest solo unit, but she might prove that title true in the "Sortie" content arriving in Season 3.

Magna/Calipe (Supporter)
. A Vanguard who is good at guarding. There is some fun to be had, but not enough to warrant an exchange. In the first place, the Vanguard role itself is not good (excluding Nine). There is almost no content where shields are important, and the current situation is so shaky that the developers themselves have stated, "There are structural limits that cannot be solved by simple numerical adjustments alone." However, elements that Vanguards excel at, such as "Shields" and "Counterattacks," are being strengthened. You don't need to exchange for them, but I think it's worth keeping their existence in the back of your mind.

Yuki (Main Attacker?)
. Even though I introduced her in the main attacker section, you should wait for adjustments. She is an AoE attacker, but there is no environment for her. It is worse than Chiron. She is so unfortunate that I even wrote an article in the past getting angry at the developers for not providing an environment where she could shine despite her concept as an AoE attacker, and then having the audacity to announce an adjustment policy saying, "We will make her able to function as a single-target attacker." If you have her, I think it's fine to try using her, but at the very least, you don't need to exchange for her.

Luke (Main Attacker)
. I don't own him, so I don't know. From a theoretical standpoint, he has synergy with Diana regarding "Bullet" cards (I think), so he might be viable as a double attacker. He is not particularly weak. I think.

Summary

• First, just shut up and pull Diana. Top meta for Season 3 (planned)

• You should save your stones for the limited Haidemari

• Make sure to properly build your 4-star supporters

• For 5-star selection: Veronica > Hugo > Nine >= Meilin > Others

• It is also an option to wait for various selections until Haidemari is implemented

That's about it.Since you'll definitely be short on development resources, just focus on Diana for now. If you get bored, you can just raise another main character. If you don't want to pull for Diana... well, you'll have to decide that for yourself. If you're playing casually, it's a game where you can pull for or use whoever you like.

Related/Reference

Roadmap up to Season 3. Season 3 looks like it will completely change the meta, which is something existing players are looking forward to.

Season 3 balance adjustments. These are mainly numerical tweaks, so you don't need to worry about them too much.

Collapse icon. All characters are definitely there!!

The most detailed information for beginners in the universe. It's reliable as a wiki, too.

If you want to check the tier list, look here. This is the one closest to my personal feelings. Just for reference.

This guy gets it (self-praise). Current Chaos Zero has a clear distinction between multi-hit and single-hit characters, but there is absolutely no distinction between single-target and multi-target characters. You don't need to select or raise Yuki. At least not right now.

They introduce the hardcore roguelike mode, the new limited-time character Haidemari, freebies, and more, so definitely check it out if you're interested.

I never expected the range of the selection ticket to expand...