3×Unit2Resource trapDefends at four under the Legend. Draws only if it dies alone, so a second unit at its battlefield costs the card as well as the bonus.
3×Unit0InformationZero Might still conquers and Holds. Its Deathknell reveals the opposing hand and adds one XP, which the opponent may decline to give you.
2×Unit–Remote developmentPlayed to base, it improves the defender without joining it. First flex cut when the sideboard offers a better body.
3×Unit3Second actionEnters at base and readies the defender, which is a second action without a second body at that battlefield.
Threats
8 cards
1×Champion4Champion ZoneAlways available, so every hand has a four-Energy unit. Six Might defending alone before a card is spent. At six XP it gains Deflect and Ganking.
3×Unit4Secondary engineGains +1 whenever she is chosen or readied, and the trigger survives the spell being countered.
3×Unit6Cross-laneCan Ambush to a battlefield holding only enemy units, which is what punishes an opponent who overcommits to breaking the Hold.
1×Unit–FinisherA finisher, never an opening plan. First cut in most matchups.
Lone-defender support
11 cards
3×Spell–Cheapest swingChoosing Irelia adds her +1 on top, so it reads as +3 and a card.
2×Spell–Isolated attackerRewards exactly the fights this deck wants: one defender, alone.
2×Spell–UncertaintyOften worth more unspent. The opponent has to price it every turn it could be there.
1×Spell–ProtectionCounters an effect that chooses your unit or Gear, not a self-buff on their side.
3×Gear–Saves the cardSaves the unit and recalls it to base. The battlefield can still be lost, and the Deathknell does not happen.
Proactive interaction
10 cards
3×Spell–Largest cheap swingThe biggest Might per Energy in the deck, and another Fervent trigger.
2×Spell–Positional removalMoves the unit rather than answering it. Against a Deathknell body, moving beats killing.
2×Spell–Interactable removalExposes your own unit to the reply. Best after the opponent has already spent interaction.
1×Spell–Two casts over timeThe Flow cast is usually worth more on a later turn than as the second half of one enormous one.
2×Spell–Before the commitmentCast it before the all-in turn. The value is the safe sequence it buys, not the one-for-one.
Legend & battlefields
4 cards
1×Legend–The engineAlone means no other friendly unit there. A second unit turns the bonus off, and a unit leaving turns it back on.
1×Battlefield–Play secondReturns a unit to hand and leaves a two-Might token, which defends at four while alone.
1×Battlefield–Play firstDraws for each other battlefield you already control, so it rewards a Hold established somewhere else first.
1×Battlefield–Defender rotationSymmetrical. Rotating a fresh unit in and the old one out keeps the new one alone.
Might, Energy and Power appear only where the guide states them; anything it leaves unstated is left blank rather than filled in with an invented value.
Sideboard · 10
2×Targeted controlCannot be chosen by enemy spells or abilities. Still loses to combat and to untargeted effects.
2×Wide low-Might boardsEnemy units with less Might deal no combat damage at its battlefield. Deliberately turns the Legend off, and is often right anyway.
2×Gear enginesIts Gear ability needs seven runes, but it is a four-Might body before then.
1×Gear theftImmediate Gear answer where Barbara is the slower, repeatable one.
1×Wide boardsTargets are locked before Fervent’s own trigger resolves. Buff first when the count matters.
1×Mind interactionRemoves a Mind card before the turn that would otherwise be answered.
1×Cheap spell decksThe third copy, for matchups where one counter is never enough.
Chosen championMaster Yi, Tempered, in every matchup. Always available from the Champion Zone, six Might defending alone, and Deflect plus Ganking at six XP.
No alternateThe sideboard carries no second Chosen Champion, so the XP plan and the Champion sequencing never change between games. §9 →
From the guide . §2 Exact Configuration
The configuration covered uses as the Chosen Champion, a full three-copy package, and as proactive interaction, and a specialised ten-card sideboard. The list is recent and internally coherent, and it already incorporates the Vendetta cards that changed the older Master Yi structure, so it is worth playing unchanged before altering anything.◆src
The registered main deck contains 40 cards including Tempered. Tempered begins in the Champion Zone, which leaves a 39-card shuffled deck.◆src
What changed from the older builds
Earlier successful Yi lists were built around a more conventional protected-body package: Fiora, main-deck , Challenge, Primal Strength, only two Hourglasses, and no Fervent package at all. One earlier branch also ran main-deck and Grim Resolve.◆src
Three become the secondary threat engine.
Three maximise ready effects.
replaces part of the older Challenge package.
supplies reusable burst through Flow.
The third Hourglass increases protection density.
and move to the sideboard, where their narrower resilience matters most.
becomes the single high-ceiling finisher.
This is not an older list with a few new cards pushed into it. It is a more explosive branch that accepts slightly less pre-board insulation in exchange for much stronger Fervent turns.
⚠ WarningOne warning when reading older lists: some of them ran The Arena’s Greatest, which is now banned in Standard. Do not copy that battlefield package.◆src