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Iron Flask

Iron Flask
  • Category: Wondrous Item
  • Rarity: Legendary

While holding this brass-stoppered iron flask, you can take a Magic action to target a creature that you can see within 60 feet of yourself. If the flask is empty and the target is native to a plane of existence other than the one you're on, the target must succeed on a DC 17 Wisdom saving throw or be trapped in the flask. If the target has been trapped by the flask before, it has Advantage on the save. Once trapped, a creature remains in the flask until released. The flask can hold only one creature at a time. A creature trapped in the flask doesn't age and doesn't need to breathe, eat, or drink.

You can take a Magic action to remove the flask's stopper and release the creature in the flask. The creature then obeys your commands for 1 hour, understanding those commands even if it doesn't know the language in which the commands are given. If you issue no commands or give the creature a command that is likely to result in its death or imprisonment, it defends itself but otherwise takes no actions. At the end of the duration, the creature acts in accordance with its normal disposition and alignment.

An Identify spell reveals if the flask contains a creature, but the only way to determine the type of creature is to open the flask. A newly discovered Iron Flask might already contain a creature chosen by the GM.

Tactical Applications​

Combat Strategy: Can capture and store extraplanar creatures, then release them to fight as allies. Exceptional for summoning powerful allies and controlling dangerous extraplanar beings.

Class Synergies:

  • Any Class: Universal utility for summoning allies and controlling extraplanar creatures
  • Summoners: Perfect for characters specializing in conjuration and ally summoning
  • Planar Specialists: Essential for characters dealing with extraplanar entities
  • Tactical Controllers: Excellent for characters requiring powerful temporary allies

Build Considerations: Requires capturing extraplanar creatures first, then can summon them as allies. Most valuable in campaigns featuring planar travel and extraplanar encounters.

Acquisition Methods​

Crafting Requirements: Requires planar binding magic, iron enchantments, and dimensional containment techniques. Creation cost 50,000+ gp and takes 6 months.

Common Sources:

  • Planar researchers and extraplanar specialists
  • Treasure hoards of powerful summoners and planar travelers
  • Commission from legendary enchanters with planar expertise
  • Found in the collections of planar scholars and dimensional researchers
  • Rewards from grateful planar organizations and extraplanar entities

Alternative Acquisition: Sometimes discovered in planar rifts or obtained from major extraplanar encounters.

Value & Trade​

Estimated Value: 75,000-150,000 gp, considered extremely rare and valuable due to planar capabilities.

Trade Considerations: Artifact-level rarity means most acquisitions involve planar politics or epic quests rather than monetary exchange.

Character Integration​

Roleplay Elements: Suggests mastery of planar magic, experience with extraplanar entities, or completion of epic planar quests.

Character Concepts:

  • Planar scholar with extraplanar entity relationships
  • Summoner specializing in powerful ally conjuration
  • Character with extensive planar travel experience
  • Researcher studying extraplanar creatures and dimensional magic

Adventure Hooks​

The Planar Capture: Missions to capture specific extraplanar creatures for research or alliance purposes.

The Dimensional War: Planar conflicts where summoned allies provide crucial battlefield advantages.

The Entity Negotiation: Diplomatic scenarios with extraplanar beings where controlled summoning demonstrates power.

The Planar Research: Academic missions where studying captured entities advances magical knowledge.

Variants & Customization​

Greater Iron Flask (Artifact): Enhanced capacity and ability to contain more powerful extraplanar entities.

Planar Master's Flask (Legendary): Includes additional planar abilities and enhanced entity control.

Specialized Containment Flask (Very Rare): Optimized for specific types of extraplanar creatures.

Specialized Variants:

  • Demon Binder's Flask: Enhanced for containing and controlling fiendish entities
  • Celestial Flask: Optimized for angelic beings and positive energy creatures
  • Elemental Flask: Specialized for elemental creatures and planar elementals

Lore & History​

Origins: Created by ancient planar researchers who needed reliable methods for studying and controlling extraplanar entities.

Historical Significance: These flasks enabled crucial planar discoveries and the development of advanced summoning techniques.

Cultural Impact: Represent the mastery of planar magic and the ability to bind and control entities from other dimensions.

Magical Craft: Demonstrates legendary understanding of planar binding and the complex enchantments required for dimensional containment.

Balancing Notes​

Introduction Timing: Appropriate for levels 12-20 when planar travel becomes common and extraplanar entities are significant.

Campaign Impact: Provides major summoning capabilities that should be central to planar campaign storylines.

Planar Consideration: Requires access to extraplanar creatures to be effective, creating natural campaign integration points.

Encounter Design​

Recommended Challenges:

  • Planar encounters where capturing entities provides long-term advantages
  • Summoning scenarios where powerful allies determine battle outcomes
  • Diplomatic missions with extraplanar beings where demonstrating control matters
  • Research expeditions where studying captured entities advances knowledge

Tactical Adjustments: Encounters must account for potential powerful extraplanar allies.

Planar Items: Plane Shift magic, Summoning equipment, and other items that affect extraplanar travel.

Summoning Equipment:

  • Items that enhance conjuration magic and ally summoning
  • Equipment for planar research and extraplanar entity interaction
  • Tools for binding and controlling summoned creatures

Complementary Equipment: Items that enhance summoning effectiveness or provide planar protection.

Roleplay Opportunities​

Planar Mastery: Characters develop expertise in extraplanar politics and dimensional magic.

Entity Relationships: Captured creatures may develop complex relationships with their captors over time.

Dimensional Politics: Access to extraplanar entities creates involvement in cosmic conflicts and planar power struggles.