A Deep Dive into AD&D 2e Spells: Alarm

1st Level Spells, Advanced Dungeons & Dragons, Old School, Spell Deep Dive, Wizard Spells

Alarm (Abjuration, Evocation)

Level: 1
Range: 10 yards
Components: V, S, M
Duration: 4 hours + 30 minutes/level
Casting Time: 1 round
Area of Effect: Up to a 20-foot cube
Saving Throw: None

Every veteran adventurer knows that the most dangerous part of a dungeon crawl isn’t the dragon—it’s the long rest. Alarm is the premier “Wizard’s Watchdog,” a 1st-level ward that ensures the party doesn’t wake up to a dagger at their throats. While often viewed as a simple utility, its ability to detect the invisible and its flexible triggers make it a masterpiece of early-game defense.

Functional Overview

The wizard enchants a specific area (a portal, stairs, or a treasure chest) to react to intruders. The spell is finely tuned to trigger for any creature larger than a common rat—specifically, anything over 3 pounds or 1/2 cubic foot in volume.

  • The Password: Upon casting, the wizard establishes a password. Any creature speaking this word can pass through the ward undetected.
  • The Alert: When triggered, the spell unleashes an audible sound for one full round. While traditionally a bell, the caster can program a specific sound (a musical chord, a short phrase, or a warning cry).
  • Detection Capabilities: The ward detects invisible, flying, levitating, gaseous, and incorporeal creatures. However, it is bypassed by those on the Ethereal or Astral planes.
  • Persistence: Unlike many spells, the sound ending does not end the spell. The ward stays active for the full duration, re-triggering every time a new qualifying creature enters the area.

Audibility Modifiers

The alarm is clearly audible within a 60-foot radius under normal conditions. However, physical barriers dampen the sound significantly:

  • Standard Door: Reduces radius by 10 feet.
  • Substantial Wall: Reduces radius by 20 feet.

Tactical Insights & Observations

  • Advanced Perimeter Intelligence: Because the alarm re-triggers for each separate intrusion, it acts as a primitive radar. A series of “pings” can tell a resting party if they are facing a lone scout or a staggered column of infantry.
  • Coded Acoustic Signals: By customizing the sound (using the material bell as the source), a wizard can set different “ringtones” for different wards. A “hawk’s cry” could signify a window breach, while a “wolf’s howl” signals the main door.
  • Anti-Stealth Radar: Since the spell detects invisible and gaseous forms, it is the most reliable way for low-level parties to pin down a hidden stalker. Even if you can’t see the enemy, the alarm tells you exactly when they’ve crossed the threshold.
  • Psychological Warfare: A wizard can program the alarm to emit a terrifying roar or a programmed shout of “GUARDS!” This can cause enemies to hesitate or flee, buying the party precious rounds to prepare.
  • The Component Vulnerability: In this interpretation, the material bell serves as the sound’s physical source. This introduces a tactical risk: if an enemy spots the bell and muffles it or casts Silence, 15′ Radius, the audible warning is neutralized.

Research & Acquisition

Alarm is a dual-school spell (Abjuration/Evocation), making it accessible to a wide range of specialists. Researching it is a standard 1st-level undertaking:

  • Research Time: 1d10 + 1 weeks.
  • Financial Investment: 100–1,000 gp.
  • Material Components: A tiny bell (not consumed) and a piece of fine silvered wire (base metal coated in silver).

Theoretical Variants

Advanced research can produce specialized versions of this early-warning system:

  • Mental Ping (Level 2): A variant that replaces the audible sound with a direct mental alert to the caster, allowing for a “silent” alarm that doesn’t alert the intruder they’ve been spotted.
  • Selective Sizing (Level 1): A version that allows the caster to set the weight threshold higher (e.g., only triggering for creatures 100lbs or heavier), preventing stray dogs or local wildlife from waking the party.
  • Flash-Alarm (Level 2): Instead of (or in addition to) a sound, the ward releases a bright burst of light, potentially outlining invisible creatures for 1 round.

The Verdict

Alarm is the ultimate force multiplier for a party’s safety. Its long duration and ability to detect nearly every form of physical presence make it an essential spell for any wizard who values their sleep—and their life.