Getting Started

Duel Studio Classic is a free, fan-made deck-building and solo-play tool dedicated to the “Classic” format of Duel Masters — the early eras of the game known in Japan as Kihon-hen (the base sets), 05, and 08. If you love the simpler, foundational version of Duel Masters, this is a place built specifically for you. It is not a general card-game app that happens to support old cards; every screen is designed around how Classic plays.

The tool does two main things. First, it gives you a deck builder that knows the Classic card pool and its rules, so you can assemble a legal 40-card deck and instantly see which regulation (base / 05 / 08) it is valid for. Second, it gives you a Solo Play mode that lets you actually shuffle and play your deck by yourself, so you can test how it really behaves before you ever sit down across from an opponent.

Two honest notes before you start. This is an unofficial, individually-run fan site — it is built and maintained by a single Classic player (handle: Meshi), not by a company or by the rights holders of Duel Masters. And the entire interface is currently in Japanese. That is exactly why this English guide exists: the buttons you will tap are written in Japanese, so below we always show you the Japanese label together with what it means, step by step. You do not need to read Japanese to follow along.

The fastest way to try Duel Studio Classic is as a guest. You do not need to create an account, install an app, or hand over an email address to get going. Everything you make as a guest is saved locally on your own device, so you can explore freely and decide later whether you want to sign in. Here is the whole flow:

1. Open the site. Load the top page in any modern browser on your phone or PC. You will land on a simple title screen rather than a login wall.
2. Tap the guest button. Look for the button labelled “ゲストとして使ってみる” (which means “Try as a Guest”). Tapping it drops you straight into the app with no further questions.
3. Your data is saved on the device. From this point on, any deck you build is stored in your browser’s local storage. It stays on that one device and is not uploaded anywhere. Closing the tab and coming back later keeps your decks intact.
4. Start building and testing immediately. As a guest you already have full access to the two core features: the deck builder and Solo Play. There is nothing locked behind a paywall for the parts that matter.
5. Sign in later only if you want to sync. Guest data lives on a single device. If you want the same decks on your phone and your PC — or you simply want a backup — you can sign in with Google or X (Twitter) at any time, and your work carries over. This step is entirely optional and you can put it off until you are sure you like the tool.

In short: tap one Japanese button, and you are in. The guest path is deliberately friction-free so that trying the tool costs you nothing. The short walkthrough below shows exactly what the screen looks like as you do this.

A Duel Masters deck is always exactly 40 cards — not 39, not 41. You may include at most four copies of any single card. Those two rules are the frame everything else fits into, and Duel Studio Classic enforces them for you automatically: it will block a 41st card and warn you when you try to add a fifth copy of something. That means you can focus on the interesting decisions instead of counting. Here is a sensible order to build your first deck in.

1. Pick your civilizations. There are five civilizations: Light, Water, Darkness, Fire, and Nature. A single-civilization deck is the most beginner-friendly because it almost never suffers from mana-color problems. A two-civilization deck is the most common choice once you are comfortable, letting one color cover the other’s weaknesses.
2. Mind the mana curve. The mana curve is how your cards are spread across costs. If it is lopsided you will draw hands where you have mana but nothing to play, or cards you cannot afford. A common starting shape is a few 1- and 2-cost cards, a strong core of 3- and 4-cost cards, and a smaller number of heavy finishers. The builder draws this curve as a bar graph so you can see imbalance at a glance.
3. Balance your civilizations’ counts. In a two-color deck, make sure you actually have enough cards of each color to pay for your spells and creatures on time. A few multi-color cards (around four to six) smooth this out and reduce the odds of a color screw.
4. Include shield triggers. Shield triggers are cards you can play for free when an opponent breaks one of your shields — your main way to claw back from an attack. Around six to ten is a typical amount; aggressive decks run fewer, control decks run more. Mixing their effects (destroy, bounce, draw, summon a blocker) makes your defense far more flexible than stacking one kind.
5. Choose your finishers. Finishers are the cards that actually close out the game — usually high-cost, high-impact creatures. Pick them by three questions: how fast do they win once they land, how easily are they removed, and can you reliably draw or search them when you need them. Two to four copies is the usual range.
6. Use the deck builder screen. Filter the card pool by civilization, cost, race, or ability (shield trigger, blocker, and so on), and tap a result to add it. The top of the screen shows whether your current deck is legal for base / 05 / 08, sorting helps you review the curve, tapping a card enlarges it so you can read its text, and restricted or banned cards are flagged so you never include one by accident.

Do not aim for a perfect deck on your first try. The fastest way to learn is to lay down 40 cards that roughly follow the points above, then refine. The walkthrough below shows the builder screen in action while assembling a deck from scratch.

Once you have 40 cards, the most valuable thing you can do is play the deck by yourself. In Solo Play you shuffle, draw your opening hand, set mana, and take turns exactly as you would in a real game — just without an opponent. Card-game players often call this “goldfishing”: you are checking how your own deck flows, not trying to win a match. Because Classic opponents are hard to find in person, this is the main way to put a deck through its paces.

• Goldfish your opening turns. Shuffle, draw five, and play out the first three turns. Repeat this ten or twenty times and you quickly feel how consistent the early game is — how often you can act on turns one, two, and three, and how often you stumble.
• Check the mana curve in practice. The bar graph in the builder is a prediction; Solo Play is the reality. Repeated draws show whether you genuinely have plays at each cost, or whether (say) your two-drop slot is too thin and leaves you stalling.
• Adjust, then test again. When a pattern of dead hands or clunky turns shows up, swap a few cards and run the deck again. This loop — play, spot the problem, tweak, replay — is what turns a rough draft into a deck you trust. The tool handles shuffling and mana math for you, so each test takes a couple of minutes instead of ten.

If you have never goldfished a deck before, build one and run it ten times. Seeing your deck’s real behavior — rather than how you imagined it — is the single biggest step up in deck-building skill.

That is the whole loop: start as a guest, build a 40-card deck, and test it in Solo Play. From here, the deeper guides go further into each piece. They are written in Japanese, but they pair naturally with what you have just learned, and the deck builder enforces the same rules described above.

• Deck Building Guide — a deeper look at the 40-card rule, civilizations, mana curve, and finishers.
• Solo Play Guide — how to get the most out of testing a deck by yourself.
• Regulation Guide — the differences between the base, 05, and 08 formats and how to choose one.
• FAQ — common questions about the tool and the Classic format.