Sleeper Island Summoning Guide

Sleeper Island uses custom rules for summoning spells, to make combat easier and provide a better experience for all players involved. 

Change 1: Minion Limit

Characters are limited to 4 minions or 4+1 if you have a familiar and/or animal companion.

Change 2: Upcasting

Upcasting spells no longer increases the number of creatures summoned.
Instead the CR maximum for the respective summons are increased by 1 per duplicate set.

Example: If it would normally double then CR+1, if it would normally triple then CR+2, if it would normally quadruple then CR+3.

CRs are rounded down to nearest whole number if the resulting CR is over 1. Single summoned creatures instead increase their CR by 1 per spell level upcasted, this is in addition to any behavior that currently exists with increasing CR when upcasting.

Change 3: Encountering creatures

The player gets the choice of what creatures are summoned. The player must have encountered the creature type before and succeeded in an arcana/religion/nature check (whichever is appropriate). The DC is equal to 10 + the creature’s CR, rounded down.

If the player does not specify a creature type, it is up to DM discretion as to what creature is summoned, if any.

Only official or third party unofficial stat block creatures can be summoned – homebrewed DM creations are exempt from your summoning attempts.

Change 4: Non-concentration Swarm Tokens 

Each swarm token can only have one creature type attached to it (e.g. zombie or skeleton but not both).
Each swarm token takes a single minion slot.

They are named “Swarm of {creature type} {number of creatures in swarm}”

Any aoe damage is multiplied by the number of creatures in the swarm.
The swarm’s number should be updated AFTER combat.

You are responsible for keeping track of this and if found to not be obeying the rules will have your summoning privileges revoked and possibly be kicked from the campaign.

They either do:

  • 1 attack roll, full damage (add total damage of all mobs together)
  • No attack roll, compare to-hit with AC (total damage = average/mob # of mobs hit %)
    Hit % = number of average hits for the mobs.

Change 5: Maximum HP

Single summoned creatures receive a maximum of their allowed hit points, when first summoned.

Change 6: Casting Time

All summoned spells require either their current casting time or a full minute casting time, whichever is longer.

To compensate, the spells durations are doubled, if the caster desires

Summoning Spells Table

Spell Name Casting Time Duration Effect
Phantom Steed 1 minute 1 hour Max HP Mount
Unseen Servant 1 minute 2 hours Duration Increase
Conjure Animals 1 minute 2 hours (C) Max HP Animal Swarm, Duration Increase, Swarm Token
Conjure Celestial 1 minute 2 hours (C) Max HP Celestial, Duration Increase
Conjure Elemental 1 minute 2 hours (C) Max HP Elemental, Duration Increase
Conjure Fey 1 minute 2 hours (C) Max HP Fey, Duration Increase
Conjure Minor Elementals 1 minute 2 hours (C) Max HP Elemental, Duration Increase, Swarm Token
Conjure Woodland Beings 1 minute 2 hours (C) Max HP Being, Duration Increase, Swarm Token
Danse Macabre 1 minute 2 hours (C) Max HP Undead, Duration Increase, Swarm Token
Infernal Calling 1 minute 2 hours (C) Max HP Devil, Duration Increase
Summon Greater Demon 1 minute 2 hours (C) Max HP Demon, Duration Increase
Summon Lesser Demons 1 minute 2 hours (C) Max HP Demon, Duration Increase
Animate Objects 1 minute 30 minutes (C) Max HP Object, Tiny and Small size not allowed, Duration Increase, Swarm Token
Bigby’s Hand 1 minute 30 minutes (C) Duration Increase only
Giant Insect 1 minute 30 minutes (C) Max HP Insect, Duration Increase, swarm token
Tiny Servant 1 minute 8 hours Max HP Servant
Animate Dead 1 minute Instantaneous Max HP Undead, Swarm Token
Bones of the Earth 1 action Instantaneous Unaffected, Not in rule scope
Create Homunculus 1 hour Instantaneous Max HP Homunculus
Create Undead 1 minute Instantaneous Max HP Undead, Swarm Token
Find Familiar 1 hour Instantaneous Unaffected
Find Greater Steed 10 minutes Instantaneous Unaffected
Find Steed 10 minutes Instantaneous Unaffected
Finger of Death 1 action Instantaneous Max HP Zombie
Mighty Fortress 1 minute Instantaneous Unaffected
Negative Energy Flood 1 action Instantaneous Max HP Undead
Planar Ally 10 minutes Instantaneous Max HP Ally
Simulacrum 12 hours Until dispelled Uneffected

Summoning Items Table

Item Name Casting Time Duration Effect
Bowl of Commanding Water Elemental 1 Minute 2 hours (C) Max HP Elemental, Duration Increase
Brazier of Commanding Fire Elemental 1 Minute 2 hours (C) Max HP Elemental, Duration Increase
Censer of Controlling Air Elemental 1 Minute 2 hours (C) Max HP Elemental, Duration Increase
Stone of Controlling Earth Elementals 1 Minute 2 hours (C) Max HP Elemental, Duration Increase
Elemental Gem, Emerald 1 Action 2 hours (C) Max HP Elemental, Duration Increase
Elemental Gem, Red Corundum 1 Action 2 hours (C) Max HP Elemental, Duration Increase
Elemental Gem, Blue Sapphire 1 Action 2 hours (C) Max HP Elemental, Duration Increase
Elemental Gem, Yellow Diamond 1 Action 2 hours (C) Max HP Elemental, Duration Increase
Bag of Tricks, Tan 1 Minute Until Dawn Max HP Creature, Duration Increase
Bag of Tricks, Gray 1 Minute Until Dawn Max HP Creature, Duration Increase
Bag of Tricks, Rust 1 Minute Until Dawn Max HP Creature, Duration Increase
Hat of Vermin 1 Action 1 hour Max HP Creature
Ring of Djinni Summoning 1 Minute 2 hours (C) Max HP Djinni, Duration Increase