Threat Economy 101: How TH, ZTC & Spawns Drive the Zombie Phase

Master the undead power curve: gain 4 TH each Zombie Phase, spend it on ZTC to spawn threats, bank what’s left (with the >6 TH → discard 1 decay rule), and time your spawns so Advance → Attack lands when it hurts most.

Why the Threat Economy matters

In NecroGenesis, the Zombie side runs on Threat Points (TH). You gain 4 TH at the start of every Zombie Phase, then spend TH to pay each zombie’s Zombie Threat Cost (ZTC) and spawn them into the Zombie Zone. How you budget TH determines the pressure curve, the size of your waves, and how reliably your board reaches the Threat Zone to attack.

The three levers

TH — your fuel

Refresh: Gain 4 TH at the start of each Zombie Phase.
Banking: Unused TH carries over.
Decay: End step — if TH > 6, discard 1 TH.
Practical cap: Ending on 6 or less avoids decay.
Tactical decay: Floating 7+ is fine if you’ll spend down next turn for a spike.

ZTC — what your threats cost

Spawn any number during Spawn as long as you can pay each ZTC.
Typical spectrum: Walkers (1), Runners (2), Brutes (3), Mutants (varies), Boss (deck max 1).
Curve building:
Low ZTC → board fill & early chip pressure.
Mid ZTC → two-turn setups that align with Advance → Attack.
High ZTC → bank TH to drop a centerpiece when defenses are thin.

Spawns — timing is everything

Spawn: Zombies enter the Zombie Zone.
Summoning Sickness: Newly spawned can’t Advance this turn (unless Fast).
Advance: Start of Advance, all in Zombie Zone move to Threat Zone (if able).
Attack: Threat Zone zombies attack.
Quick Escape: Survivor may spend 1 TP once per Zombie Phase to roll vs ED and negate one attack on success.

Example curves (clean numbers)

Curve A — “Always on” pressure

Turn N (start @ 0 TH): Gain 4 → 4 TH. Spawn Brute (3) → bank 1.
Turn N+1: Gain 4 → 5 TH. Spawn Runner (2) + Walker (1) → bank 2.
Turn N+2: Gain 4 → 6 TH. Spawn Brute (3) + Walker (1) → bank 2 again.

Why it works: You avoid decay and keep a steady lane marching Zombie Zone → Threat Zone.

Curve B — “Save for the hammer”

Turn N (start @ 2 TH): Gain 4 → 6 TH. Pass (no spawns).
Turn N+1: Gain 4 → 10 TH → spend Boss (7) + Walker (1) → end on 2 TH (no decay).

Why it works: You accept a quiet turn to cash in a high-ZTC threat next turn, dodging decay by spending at the right moment.

Curve C — “Staggered waves”

Turn N: Spend 4 TH on four Walkers (they don’t Advance yet).
Turn N+1: Those Walkers Advance → Attack; spawn 2 Runners (4 TH) to set up next turn’s Advance.

Why it works: One wave hits while the next assembles; Survivor can only Quick Escape once.

Practical tips

End on ≤6 TH to avoid decay—unless you’re deliberately banking for a spike.
Spawn before you want to strike. Attackers must already be in the Zombie Zone the turn prior.
Mix ZTC bands. A mid-ZTC plus a couple of lows often beats one huge body into an empty board.
Play around Quick Escape: force multiple attackers so negating one still leaves damage.
Count AP/TP: if the Survivor just spent heavily, push a higher-ZTC threat window.

One-page checklist (Zombie Phase)

Gain 4 TH (carry over any banked TH).
Spawn by paying ZTC (any number).
Advance all zombies already in the Zombie Zone.
Attack with zombies in the Threat Zone (Survivor may Quick Escape once).
End step: If TH > 6, discard 1 TH.

Master these three levers—TH flow, ZTC curve, and spawn timing—and your undead will feel relentless, measured, and brutally efficient.

Leonardo AI Art Prompts (optional)

1) Hero image (16:9)

Prompt: Biopunk tabletop key art for a zombie TCG “Threat Economy” turn (no readable text/numbers). Two neon lanes on a premium dark board: far Zombie Zone and mid Threat Zone, separated by crisp emerald seams. Focal point: a single hand-drawn, ink/pencil–sketched zombie mid-landing on the front edge of the Threat Zone—one foot striking down with a subtle dust ring and motion lines. Behind it, faint spawn shimmer in the Zombie Zone. To the left: small stack of holographic emerald TH counters; near the far lane, tiny hovering cost-chips imply ZTC (no numbers). A single tiny shield glyph near the front attacker hints the once-per-phase Quick Escape. Palette: emerald #16C233 and mint #A1FFB0 accents over obsidian charcoal; soft bloom, micro-particles, light fog, cinematic rim light. Ultra-detailed digital painting blended with a tasteful sketch overlay on the zombie, sharp focus, clean negative space on the RIGHT for headline.

Negative: text, letters, numbers, UI copy, logos, watermark, gore, dismemberment, cartoon, lowres, blurry, border, frame, overexposed

Settings: 16:9 • cinematic concept-art • cool ambient + emerald rim • ~35mm • CFG 7–9

2) Thumbnail / list card (1:1)

Prompt: Minimal biopunk emblem for “Threat Economy”: a sketched zombie silhouette (ink cross-hatch) touching down on the front of a two-lane board icon; thin emerald lane seams; small stack of holographic TH counters on the left; tiny hovering cost-chip near the far lane; a single tiny shield glyph near the front lane. Glossy emerald #16C233 / mint #A1FFB0 on matte charcoal, crisp, no text.

Negative: text, logo, numbers, watermark, gore, clutter, lowres

Settings: 1:1 • CFG 7–9 • High detail, soft bloom

3) Flow banner (21:9)

Prompt: Wide biopunk process graphic (no text): left stack of emerald TH counters → cost-chips (ZTC) → ink-sketched zombie materializing in the far lane (spawn) → arrow into mid lane where it lands with a subtle dust ring (advance) → front edge impact glow (attack). Emerald/mint highlights on charcoal, neon seams, scanline sheen, clean composition.

Negative: text, numbers, logo, watermark, gore, clutter

Settings: 21:9 • CFG 7–9

4) “Three Levers” graphic

Prompt: Triptych with no text: Panel A (TH) emerald counters with soft refresh glow and faint decay ripple; Panel B (ZTC) cost-chips beside small/medium/large zombie silhouettes; Panel C (Timing) hand-sketched zombie wave—front figure landing in the mid lane while a second sketched wave sits in the far lane. Consistent emerald/mint on deep charcoal, subtle bloom/particles.

Negative: text, numbers, logo, watermark, gore, border

Settings: 4:3 or 16:9 • CFG 7–9