Isekai Zero vs OOC vs Mythx AI (2026): Credits, Memory & Art

If you've seen the ads for OOC ("The Playable Anime") and hit its credit wall, you've probably heard of Isekai Zero next: another AI anime story game, with a visual-novel mode and a very different price. Both are free to start, both run on credits, and neither has a subscription. This comparison is written by the maker of a third app, Mythx AI, so read it knowing that. Neither OOC nor Isekai Zero is ours; we've checked every fact about them against their own sites and store listings as of September 30, 2026.

TL;DR

• Cheaper per message: Isekai Zero, by a wide margin on its budget models. Its own pricing says $1 buys "up to 1,000 full memory RP messages" on DeepSeek v4 Flash. An OOC story message costs 30 to 90 credits — about 4 to 13 cents at App Store prices.
• Free forever, one-on-one: OOC's Character mode offers "Free Unlimited Chat" on its Basic model.
• The visual novel: Isekai Zero's optional visual-novel mode adds scene art, voice narration and changing expressions, each for a few credits.
• No meter at all: Mythx AI gives free gems every day and a flat Premium plan, with an image in every scene included. It's our app — weigh that.

What each one is

OOC: The Playable Anime is made by New AI Entertainment Inc. It calls itself "the first interactive anime" and has two modes: Story, where you play a persona inside an anime world, and Character, where you chat one-on-one. Players can create and publish their own stories and characters. It runs on the web at ooc.ai and in iOS and Android apps.

Isekai Zero is an "AI Visual Novel & Adventure" game where you're transported into anime worlds. Its App Store listing promises "stories with actual endings," and creators "earn a 25% profit share whenever other players play your worlds." It runs on the web at isekaizero.ai and in iOS and Android apps.

Mythx AI is our AI roleplay game. Instead of a library of stories, you arrive as the newcomer in one of a set of living worlds — a Japanese academy, a magic academy, a Victorian city, a fantasy tavern and more — where the cast has jobs, routines and a memory of you, and every scene comes with an AI-generated image.

Price: what a message costs

This is the question most people searching "Isekai Zero vs OOC" want answered.

OOC sells credits. On the App Store, packs run from 1,000 credits for $1.39 to 100,000 for $142.99; its help center says web prices can be lower because they skip app-store fees. A Story message costs 30 credits on the Basic model, 60 on Skillful or Extensive, and 90 on Superb, with extra credits for replies longer than 800 tokens. Premium Mode in Character chat is 20 credits per use.

Isekai Zero sells Arcane at a base rate of "100 Arcane = $1 USD" — about $1.10 per 100 on its website and $1.34 in the app stores, according to its transparent pricing page. Cost depends on the model you pick: its own example is that $1 on DeepSeek v4 Flash buys "up to 1,000 full memory RP messages." Premium models cost more and take Arcane only. There's also Mana, a free currency you earn from daily check-ins and ads, which covers standard models first.

What you pay	OOC	Isekai Zero
Currency	Credits	Arcane (paid) + Mana (free, earned)
Smallest App Store pack	$1.39 for 1,000 credits	$2.99
One story message	30–90 credits (≈ $0.04–$0.13 at the 10,000-credit App Store pack)	Up to 1,000 messages per $1 on DeepSeek v4 Flash; more on premium models
Cheaper on the web?	Yes	Yes (~$1.10 vs ~$1.34 per 100 Arcane)
Subscription	None	None

Mythx AI works differently: you start with free gems and get more every day, and Premium is $4.99 a week, $9.99 a month or $79.99 a year for unlimited story and 100 illustrated scenes a day — one price, whatever you play. See pricing.

Free play

OOC's App Store listing offers "Free Unlimited Chat," but only "using the Basic Model in Character Mode." Story mode uses credits. Its developer says in App Store replies that players get 300 free credits a day — about ten Basic story messages, or three on Superb — and its help center notes that "free credits expire 30 days after being issued." That daily allowance is the most common complaint in its reviews.

Isekai Zero's free currency is Mana, earned from check-ins and ads. It "cannot be purchased directly," and it's spent before Arcane on standard models. How far it goes depends on the model you pick.

On Mythx, free gems arrive every day, and the images are part of each scene rather than an extra.

Memory and stories

OOC's App Store listing promises "companions that truly remember your shared history and grow with you." Isekai Zero leans hard on memory in its pricing: "No Memory Caps," and you can "adjust context size to whatever your appetite allows" — bigger context simply costs more per message. In practice, players of both report stories drifting on long runs; that's still the hardest problem in AI roleplay.

The bigger difference is shape. Isekai Zero's stories are built to end, like a visual novel. OOC's Story mode is open-ended persona play. Mythx takes a third route: the world itself persists — places, a running clock, and characters who remember you across sessions — so there's no ending to reach and no reset.

Images, voice and music

Isekai Zero has the richest presentation of the three, with a catch. Its visual-novel mode is optional — plain narration is the default — and marked "Experimental - Public Beta." Turned on, it generates backgrounds and characters (about 0.6–0.7 Mana or Arcane per image), new expressions and poses (2 per edit) and voice narration in each character's voice (1–2 per narration). Its App Store listing adds "a soundtrack that follows the mood."

OOC shows scene images in its stories: by default the AI picks one from the art the story's creator uploaded, and you can tap to generate a new one in real time.

Mythx AI generates an image for every scene automatically, and characters keep the same face and outfit from scene to scene. It doesn't do voice or music.

Hoshimori, the Mythx world set at a Japanese academy.

Library and creators

Both OOC and Isekai Zero are built on player-made content. Isekai Zero pays creators a 25% profit share on the Arcane players spend in their worlds. OOC lets anyone publish stories and characters, and buys the rights to a few as "OOC Originals" — $300 plus a 2% revenue share.

Mythx has no community library or builder. You play our worlds, with a hero you can design. That's a real gap if browsing new stories every night is the fun.

Platforms and age ratings

All three run in the browser and in iOS and Android apps. In the App Store, OOC is rated 13+ (4.6 stars from 6.6K ratings) and Isekai Zero 16+ (4.8 stars from 804 ratings), as of September 30, 2026. Mythx AI is a filtered app.

Quick comparison

	OOC	Isekai Zero	Mythx AI (ours)
Format	Story + 1:1 character chat	Visual-novel stories + chat	Living worlds you arrive in
How you pay	Credits per message	Arcane per use, free Mana	Free daily gems, flat Premium
Subscription	No	No	Yes — $9.99/mo
Free play	Unlimited Basic character chat; daily credits	Mana from check-ins and ads	Free gems every day
Images	Creator art, or generate on tap	In visual-novel mode, per image	Every scene, included
Voice and music	—	Voice narration, soundtrack	No
Stories	Open-ended	Built to end	World persists
Player-made content	Yes	Yes, 25% profit share	No
Platforms	Web, iOS, Android	Web, iOS, Android	Web, iOS, Android

A dash means the product's own pages don't say, so we haven't claimed it.

Pick OOC if…

• You mostly want one-on-one character chat, and free unlimited chat on the Basic model is enough.
• You like its anime story catalog and don't mind paying per story message.

Pick Isekai Zero if…

• Price per message matters most — its budget models are far cheaper than OOC's story modes.
• You want the full visual novel: art, voice, changing expressions and a soundtrack.
• You like stories with real endings, and you'd like to be paid for the worlds you build.

Pick Mythx AI if…

• You're tired of watching a meter, and a flat plan with free daily gems sounds better.
• You want a picture of every scene, with characters who look the same every time.
• You'd rather live in one world that remembers you than start a new story each night. Try the isekai-style opening, or browse the worlds.

Apps like OOC

If you searched for apps like OOC (or "OCC"), the closest matches are Isekai Zero for anime visual novels and Mythx AI for illustrated worlds on a flat plan. For character chat, Character.AI and Janitor AI are the big libraries, and Talkie adds character art and voices. Our Isekai Zero alternatives and Character AI alternatives guides cover the wider field.

Common questions

Is Isekai Zero cheaper than OOC? Usually, yes. Isekai Zero's own example is up to 1,000 messages for $1 on DeepSeek v4 Flash, while an OOC story message costs 30 to 90 credits — about 4 to 13 cents at App Store pack prices. Premium models on Isekai Zero cost more, so it depends on what you pick.

Is OOC free? Partly. Character mode on the Basic model is free and unlimited. Story mode uses credits, and daily free credits cover only a few messages.

Does either have a subscription? No. Both sell currency packs. Mythx AI is the option here with a flat subscription.

Is OOC on PC? Yes — it has a web version at ooc.ai as well as iOS and Android apps. So does Isekai Zero, at isekaizero.ai.

Which has better art? Isekai Zero's visual-novel mode adds scene art, voice and changing expressions, each for a few credits. Mythx AI puts an image in every scene automatically, with consistent characters. OOC shows its creators' scene art and can generate a new image when you tap.

The bottom line

OOC and Isekai Zero are close cousins: anime stories, creator libraries and credits. Isekai Zero is cheaper per message and goes further on presentation; OOC is simpler, with free unlimited character chat on its Basic model. If what you really want is to stop counting credits — and to see every scene — Mythx AI is the third option: free gems every day, a flat plan, and a world that remembers you. Play Mythx AI free in your browser.