Ready-to-run 30-minute adventure

d&d one shot for 2 players 30 minutes

Two Keys at Blackglass Gate: A two-character heist where both heroes must split attention, trade keys, and trust each other under a hard clock.

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Level 2
2 players
30 minutes
Tense tiny heist

Adventure Hook

A prison gate made of black glass will open for exactly one minute at moonrise. Two keys are needed at the same time, and they are held by rival ghosts who refuse to be in the same room.

Read-Aloud Opening

“Blackglass Gate stands in the cemetery wall, reflecting a moon that has not risen yet. Two keyholes wait side by side. From the east crypt comes violin music. From the west ossuary comes the scrape of a shovel. You have thirty minutes before the gate opens without you.”

DM Brief

  • Write each player a spotlight: one social/clever ghost scene and one physical/danger scene. Swap who gets which if their characters fit better.
  • Cut between players like a show: 'Meanwhile, at the east crypt...' keeps two-player play energetic.
  • The finale only works when both players act together, so reinforce communication and trust.

30-Minute Pacing Notes

  • 0:00–4:00 ask each player why they need what waits behind Blackglass Gate.
  • 4:00–12:00 Scene 1 gives Player A the talking ghost and Player B the dangerous key; then switch attention every two minutes.
  • 12:00–21:00 Scene 2 forces them to trade information, items, or positions.
  • 21:00–30:00 Scene 3 is simultaneous action at both keyholes; count rounds out loud for tension.

Clip-Worthy Moments

  • Both ghosts insult each other through the players as unwilling messengers.
  • A key turns into a black-glass moth and must be caught without crushing it.
  • The two heroes see each other reflected as children, rivals, or future legends in the gate.
  • Final beat: both players say what they unlock at the exact same time.

Scene 1 — Ghosts Who Won't Share

8 minutes

“The east crypt smells of roses and old music. The west ossuary smells of rain and turned earth. Each ghost says the same thing first: 'Do not trust the other one.'”

Goal: Give each player a separate problem and a reason to coordinate.

What Happens

  • • Lady Merrow in the east crypt has the Moon Key but only gives it to someone who proves the other ghost lied.
  • • Gravekeeper Toll in the west ossuary has the Grave Key but is trapped under a fallen angel statue.
  • • Both ghosts are partly wrong: they betrayed each other once, then each forgot why.

Checks

  • • Persuasion or Insight DC 12 gets a ghost to admit one piece of the shared story.
  • • Athletics DC 12 or Mason's Tools DC 11 frees Toll without cracking the Grave Key.
Fail forward: If a check fails, the player still gets a key, but it carries a grudge that becomes a complication in Scene 3.

Scene 2 — The Blackglass Moths

9 minutes

“Both keys shiver. Wings unfold from their teeth. The keys become black-glass moths and flutter toward the wrong crypts.”

Goal: Make the two players solve a moving problem together.

What Happens

  • • Each moth flies toward the ghost who does not own it. The players must decide whether to chase, trade, or use the ghosts as bait.
  • • A moth caught gently remains a key; a moth crushed still works but releases a glass shard swarm.
  • • Let each player make one primary action, then resolve consequences fast.

Checks

  • • Acrobatics or Sleight of Hand DC 12 catches a moth without damage.
  • • Performance or Intimidation DC 12 makes both ghosts stop arguing for one round.
Fail forward: On failure, the keys are recovered, but one Glass Shard Swarm appears at the gate during Scene 3.

Scene 3 — One Minute at Moonrise

13 minutes

“Moonlight touches Blackglass Gate. The two keyholes glow. Reflections crowd the glass from the other side, pressing pale hands against the door.”

Goal: Finish with simultaneous teamwork and a compact fight if needed.

What Happens

  • • The heroes must stand at separate keyholes and spend the same round turning both keys.
  • • If either key holds a grudge from Scene 1, that player must speak one sentence of forgiveness or truth before it turns.
  • • The Gate Warden attacks anyone who tries to force the gate or delay moonrise, but it can be distracted by a ghost's apology.

Checks

  • • Arcana or Religion DC 12 synchronizes the key turn if the players are separated.
  • • Persuasion DC 13 convinces Merrow and Toll to apologize, stunning the Gate Warden for one round.
Fail forward: If the minute passes, the gate opens halfway. The heroes get what they came for, but something small and mirror-eyed follows them home.

Stat Blocks

Gate Warden

AC 14 · HP 28 · Speed 30 ft.

Traits

  • • Two-Key Lock: it has resistance to weapon damage until both keys have been turned once.
  • • Reflected Guard: opportunity attacks against it have disadvantage while it stands within 10 feet of Blackglass Gate.

Actions

  • • Glass Halberd: +4 to hit, reach 10 ft., 7 slashing damage.
  • • Lockstep, recharge 5–6: both heroes make a DC 12 Strength save or are pushed 10 feet away from their keyholes.

Glass Shard Swarm

AC 13 · HP 10 · Speed 0 ft., fly 30 ft. (hover)

Traits

  • • Swarm: can occupy another creature's space.
  • • Brittle: takes double damage from thunder or bludgeoning damage.

Actions

  • • Cutting Cloud: +4 to hit, reach 0 ft., one creature in its space takes 5 slashing damage.

Rewards

  • Behind the gate is the exact object each hero named at the start, plus a shared black-glass token worth 40 gp.
  • If the ghosts reconcile, they become harmless advisors who can answer one cemetery-related question per month.

Scaling Notes

  • For brand-new players, remove the Gate Warden's resistance and run the moths as pure skill checks.
  • For optimized characters, add one Glass Shard Swarm at the start and another if a key is crushed.