Multiverse Reforged

Jace, Multiverse Architect

−3 exiles another target creature or planeswalker you control, then reveals until a creature OR planeswalker card and puts it directly onto the battlefield. +1 draws two, then bottoms a card -- real hand and hit-pool repair. The broader hit pool (creature or planeswalker) is Jace's main edge over Nissa.

Nissa, Leyline Tamer

Landfall draws a card on every land entry. Only the first time that ability resolves each turn does it reveal until a creature card (not planeswalkers) and put it onto the battlefield -- later land drops that same turn still draw, but do not convert. Her priority shifts toward land-drop density, not fodder generation.

Omnath, Locus of the Void

A 6/6+ body that's a legal hit for both Jace's −3 (creature or planeswalker) and Nissa's Landfall (creature only).

Hit eligibility: Eligible for both Jace and Nissa.

Trade-off: Possible weak hit: Omnath has no ETB trigger, so being put into play mid-turn (rather than resolving normally with mana already committed) often just gets a plain body with no immediate impact.

Dack Fayden, Helping Hand

His ETB reveals and battlefield-places creatures for you -- but then goads them and hands control to your opponents.

Hit eligibility: Eligible for both Jace and Nissa.

Trade-off: Unresolved: the ETB fires normally whether cast or put into play, so this is a real, board-state-dependent risk, not just a setup aid or a guaranteed good hit.

Ob Nixilis, the Ascended

ETB one-sided board wipe against tapped opponent creatures, plus lifegain.

Hit eligibility: Eligible for both Jace and Nissa.

Trade-off: Desirable threat: the ETB triggers on any entry, so it's a strong hit regardless of how it's put into play.

Avacyn, Angel of Horror

8/8 flying deathtouch with a recursion static ability that works the moment she's on the battlefield.

Hit eligibility: Eligible for both Jace and Nissa.

Trade-off: Desirable threat: no ETB dependency, so her value is immediate either way.

Elspeth, Sun's Champion

A planeswalker hit that also refills the board.

Hit eligibility: Eligible for Jace's −3 (creature or planeswalker) only -- Nissa's Landfall only finds creature cards.

Trade-off: Desirable threat, and the one clean example of why Jace's broader hit pool (creature or planeswalker) differs from Nissa's.

Memnarch, the Warden

Indestructible body whose ETB (two Myr tokens) fires on any entry.

Hit eligibility: Eligible for both Jace and Nissa.

Trade-off: Desirable threat: resilient and has immediate value regardless of entry method.

Protect the hit pool and the engine

• Sensei's Divining Top: Setup aid: lets you look at and rearrange the top card before a −3 reveal sequence, protecting a curated hit pool.
• Scroll Rack: Setup aid: exchanges hand cards with the top of the library, another way to push an accidental hit-pool card out of the way.
• Ugin, the Spirit Dragon: Desirable threat: colorless, so it's a legal hit in this WUBR deck without diluting the color identity, and a one-sided board wipe once it lands.
• Bitterblossom: Setup aid: a repeatable disposable-token source, so −3 fodder never has to come from a real card.
• Swiftfoot Boots: Protection: keeps Jace alive long enough to reach −3 again, without adding a creature that could itself become a weak hit.
• Mystical Tutor: Finds an instant or sorcery such as Mass Polymorph, Synthetic Destiny or protection and puts it on top. It doesn't stack a creature or planeswalker for Jace or Nissa to hit, and it shuffles, so use it before Top or Scroll Rack setup, not after.
• Scrollshift: Flexible ETB and protection: blinks your own Archon of Cruelty, Ob Nixilis, Overlord of the Mistmoors or Memnarch for a second enter trigger, or saves a hit from removal, then draws a card. An instant, so it never becomes a hit.

Trigger Landfall more often

• Archaeomancer's Map: White. Puts a land from your hand onto the battlefield whenever an opponent with more lands plays one -- extra Landfall entries on other players' turns.
• Crucible of Worlds: Land recursion feeds repeat Landfall triggers turn after turn, not just once.
• Walking Atlas: Unresolved trade-off: enables an extra (even off-turn) land drop, but is itself a low-impact creature if Nissa's own conversion reveals it as the hit -- a direct example of the deck's central tension.

Lean into loyalty instead

Proliferate makes Jace reach −3 faster and more often. The cost is hit quality: the creatures here can be revealed instead of a big payoff. With only two planeswalkers in the stock 100, this mostly speeds up Jace himself.

• Ichormoon Gauntlet: Gives your planeswalkers "0: Proliferate", and each noncreature spell you cast adds another counter of a kind already on a target permanent, such as loyalty on Jace. An artifact, so it never becomes a hit.
• Tekuthal, Inquiry Dominus: Makes each proliferate happen twice. It needs a proliferate source like Gauntlet or Viral Drake, and it's a creature, so it can be a weak hit.
• Viral Drake: A repeatable {3}{U} proliferate. It's a creature, so it can be a weak hit.
• Jace, Vryn's Prodigy: Loots early and can transform into a second Jace planeswalker. The front face is a creature, so it's a small hit if revealed.

What the new legends actually do together

• Dack Fayden, Helping Hand + Venser, Fervent Forger (Both in the box · loop needs a payoff): If Dack reveals Venser, Venser's enter trigger resolves after Dack hands it to an opponent, so it can copy that donated Venser; each new Venser token can copy it again. Point a copy at another opponent's permanent to get value. Dack's reveal is random, so this is not a reliable win.
• Darksteel Angel + Putrid Goblin + Ashnod's Altar (Angel in the box · Goblin and Altar are upgrades · combo): Darksteel Angel stops -1/-1 counters, so Putrid Goblin keeps persisting. Sacrifice it to Ashnod's Altar for unlimited colorless mana and death triggers. Removing the Angel or exiling the Goblin stops it.
• Niv-Mizzet, Ghost Counsel + Reward the Faithful (Niv in the box · Reward is an upgrade · one-shot): Target yourself, gain life equal to your greatest mana value, then pay it through Niv to draw that many cards.
• Niv-Mizzet, Ghost Counsel + Words of Worship (Niv in the box · Words is an upgrade · finite engine): Each {1} turns one draw into 5 life and five draws. It stops when you run out of mana or cards.
• Ginger, Queen of Sweets + Academy Manufactor (Ginger in the box · Manufactor is an alternate build): Manufactor replaces each Gingerbrute with a normal Clue, Food, and Treasure: more resources, but no hasty creature. Not a strict upgrade.