How to Play the Union Arena Sword Art Online Yellow Deck – Integrity Knights Guide

Hey everyone, Mabi here! If you’ve been following my channel or website, you know I’ve been diving deep into Union Arena lately — and today I want to break down what might be my favorite build so far: the Yellow Sword Art Online Integrity Knights deck. This build is surprisingly balanced, easy to pilot, and rewards smart plays around its central trio: Kirito, Alice, and Eugeo.

If you’re looking for a beginner-friendly, low-gimmick, high-synergy deck that still packs a punch, this is it. Let’s jump into how it works, what to watch for, and how you can start dominating your local Union Arena tables with Integrity Knights.

🧠 The Game Plan: Balance Between Offense and Defense

This deck revolves around fielding all three main characters: Alice (aggression), Eugeo (defense), and Kirito (support). A lot of your abilities kick in only when two or more of them are present, so early-game consistency and backline management are key.

Once you hit your stride, you’ll get bonus BP, double attacks, card draw, and board control triggers — all while looping cards into your hand or onto the raid zone.

🔁 Core Characters

Alice is your primary attacker and raid engine. You’re running multiple versions, most of them with “Step” so they can swing early and become energy later.

Eugeo is defensive — boosting BP, reactivating units, and protecting your other key characters. Many of his cards are zero or low-cost, making him a great early play.

Kirito connects everything. He supports the other two, enables combo attacks, and has a Double Attack version that gets serious value when paired with Eugeo’s buffs.

🧩 Full Deck List (Text Version)

Main Characters

• 4x Alice, Synthesis 30 (0-cost, 1500 BP)
• 4x Eugeo (0-cost, 500 BP)
• 4x Kirito (0-cost, 2000 BP, Step)

Aggro & Utility Units

• 4x Alice, Synthesis 30 (1-cost, 2500 BP, Step)
• 4x Eugeo (2-cost, 3000 BP, search Kirito/Alice)
• 4x Tiese (2-cost, 2500 BP, generates 2 energy)
• 2x Fanatio (3-cost, 3000 BP, draw/discard)

Higher Cost Power Plays

• 4x Alice (4-cost, 4000 BP, Step, +1000 BP if trio present)
• 4x Kirito (4-cost, 3500 BP, Double Attack if trio present)
• 4x Eugeo, Synthesis 32 (4-cost, Impact, defensive raid)
• 4x Alice, Synthesis 35 (5-cost, KO based on field trio)

Specials & Actions

• 4x Osmanthus Blade (Special, sideline 3K/5K)
• 4x Homemade Pie (Action, refresh AP, heal on trigger)

🔍 Key Combos & Interactions

Kirito + Eugeo Combo: Boost Kirito’s Double Attack with Eugeo’s on-play buff. Now you’re swinging for 4,500 BP twice.

Step + Backline Energy: Use “Step” characters to attack early, then rotate them into energy with smart AP planning.

Raid Efficiency: Many Alice and Eugeo cards have excellent raid triggers. Don’t be afraid to raid just to keep the trio online.

✅ Strengths

Simple and Clean: No wild mechanics. Just synergy and stats.

Flexible Curve: Options from 0-cost to 5-cost keep your hand flowing.

Beginner Friendly: Great for learning Union Arena’s raid and BP systems.

⚠️ Weaknesses

Synergy Reliant: If your opponent snipes Kirito early, your bonuses disappear.

Low Trigger Power: Most cards don’t have strong on-play triggers.

Potential for Bricking: Too many high-cost units early can clog your hand.

🔧 Tips for New Players

Mulligan for a mix of Step units and low-cost Eugeos.

Prioritize building your trio early — even if that means raiding a weaker unit.

Save your Homemade Pie triggers for late-game pushes when AP is tight.

💬 Final Thoughts

This deck is simple, honest, and really fun to play. You’re not cheesing your way through games — you’re making clean, smart plays that reward good sequencing and field control.

If you’re new to Union Arena, or just love Sword Art Online, I can’t recommend this Integrity Knights build enough. It’s a great entry point into the game and has solid upgrade potential.

Thanks for reading! If you want more decks like this, check out MabiTCG.com for all the profiles we cover on the channel — and even more that we don’t get to.

Let me know in the comments or on YouTube if you’re playing SAO Yellow, and I’ll catch you in the next guide!

— Mabi