Spell-eating Ooze

Medium ooze
Challenge

STR
2
DEX
−2
CON
3
INT
2
WIS
−2
CHA
−5

37
5d8+15
14
Soak
1
Fort
+4
Ref
+1
Will
+0
Defense note natural armor
Condition immunities bleeding, blinded, charmed, deafened, exhausted, frightened, prone

Speed 4 m., climb 4 m.
Skills Arcana +3 (14)
Senses blindsight 10 m. (blind beyond this radius)

Amorphous. The spell-eating ooze can move through a space as narrow as 2 centimeters wide without squeezing.

Magic Resistance. The spell-eating ooze has advantage on saving throws against spells and other magical effects.

Spellcasting. The spell-eating ooze uses Arcana (int) to cast spells (spell save Difficulty 12, +3 to hit with spell attacks). It has 2 mana, a mana limit of 1, regains all expended mana when it finishes a long rest, and regains half its total mana when it finishes a short rest. It knows the following spells:

Cantrips (at will): spell ward

1 mana: dampen spell, detect magic, mana burn, nondetection, purge, silence

Spider Climb. The spell-eating ooze can climb difficult surfaces, including upside down on ceilings, without needing to make a skill check.

Actions (1)

Pseudopod. Melee Weapon Attack: +3 to hit. Hit: 5 (1d6 + 2) bludgeoning damage plus 7 (2d6) acid damage and the target’s armor or natural armor is corroded 1 until the end of the ooze’s next turn. The creature must make a Difficulty 12 Will saving throw. On a failure, if the creature has mana, it loses 1 mana (its choice), takes 2d6 force damage, and has disadvantage on saving throws to maintain concentration on a spell until the start of its next turn.

Reactions

Split. When an ooze that is Medium or larger is subjected to lightning or slashing damage, it splits into two new oozes if it has at least 10 health. Each new ooze has health equal to half the original ooze’s, rounded down. New oozes are one size smaller than the original ooze.

Underdarkhomebrew

Spells

As an action, you extend your hand and trace a sigil of warding in the air. Until the start of your next turn, you make the first saving throw against a spell with advantage.

As a reaction, which you use when a creature that you can touch or see within 10 meters casts a spell, you can dampen the spell, making it easier to avoid or resist. The attack is made with disadvantage or each creature makes the first saving throw against the spell with advantage. You can do so after the roll but before any effects of the roll occur.

If the roll already has advantage or disadvantage, you cannot apply another instance of advantage or disadvantage and you must use this before the roll to cancel out any advantage or disadvantage.

Augment

Counterspell. You can expend 1 additional mana to attempt to interrupt the spell instead of dampen it. Make a skill check using your spellcasting skill. The Difficulty equals the creature’s spell Difficulty + the spell’s effective mana. If you have identified the spell being cast, you have advantage on this skill check.

On a success, the creature’s spell fails and has no effect.

On a failure, you dampen the spell as normal.

A spell’s effective mana is normally the amount of mana it was cast with, including augmentation. If a feature lets a spell be cast without expending mana then the spell’s effective mana is its normal mana cost.

You gain a +1 bonus to your skill check for each additional mana expended.

(ritual); concentration, 5 minutes/mana

As an action, you sense the presence of magic within 5 meters of you. If you sense magic in this way, you can use an action to see a faint aura around any visible creature or object in the area that bears magic, and you learn its theme, if any.

The spell can penetrate most barriers, but it is blocked by 30 centimeters of stone, 2 centimeters of common metal, a thin sheet of lead, or 1 meter of wood or dirt.

If you touch a creature or object for 5 minutes, you can determine the magic affecting it. If it is a magic item or some other magic-imbued object, you learn its properties and how to use them, whether it requires attunement to use, and how many charges it has, if any. You learn whether any spells are affecting the item and what they are. If the item was created by a spell, you learn which spell created it. If it is a creature, you learn what spells, if any, are currently affecting it.

As an action, you pull magical energy out of a creature that you can touch or see within 10 meters. The creature must make a Will saving throw. If the creature doesn’t have mana or ki, the spell has no effect on it.

On a failure, it takes 1d10 force damage, loses 1 mana or 2 ki, and has disadvantage on saving throws to maintain concentration on a spell until the end of its next turn.

On a critical failure, it takes twice as much damage.

On a success, it takes half as much damage.

On a critical success, it takes no damage.

If the creature has innate spellcasting with a set amount each day, use the highest level slot from that section to determine if the slot is lost.

Augment
You can augment this spell with the following options, expending mana for each option.
  • You can increase the damage by 3d10 and the target loses 1 additional mana for each additional mana expended.

  • Antimagic Rebuke. You can expend 1 additional mana to cast the spell as a reaction, which you use when a creature that you can touch or see within 5 meters of you succeeds on a saving throw against a spell. The spellcaster is the target, the damage changes to 1d6, and additional augments increase the damage by 2d6 instead of the normal increase.

3 hours/mana

As an action, you hide yourself from divination magic. You can’t be targeted by any divination magic, perceived through magical scrying sensors, or detected by any locate spell.

Augment
You can augment this spell with the following options, expending mana for each option.
  • You can expend 1 additional mana to hide two targets that you touch from divination magic. A target can be a willing creature or a place or an object no larger than 2 meters in any dimension. You can target one additional target for each additional mana expended.

  • Sequester. You can expend 1 additional mana and consume powder composed of diamond, emerald, ruby, and sapphire dust worth 5,000 sp to hide the target creature or object until the spell is dispelled. When you cast the spell and touch the target, it also becomes invisible.

    If the target is a creature, it falls into a state of suspended animation. Time ceases to flow for it, and it doesn’t grow older.

    You can set a condition for the spell to end early. The condition can be anything you choose, but it must occur or be visible within 2 kilometers of the target. Examples include “after 1,000 years” or “when the tarrasque awakens.” This spell also ends if the target takes any damage.

As an action, a creature that you can touch or see within 10 meters can immediately repeat a saving throw against a magical effect afflicting it.

(ritual); concentration, 1 minute/mana

As an action, no sound can pass through a sphere that surrounds you. Until the spell ends, the sphere moves with you, centered on you.

Any creature or object entirely inside the sphere is immune to concussion damage that originates outside the sphere.

Casting this spell on the same spot every day for a year makes this effect permanent on that spot.

Augment
You can augment this spell with the following options, expending mana for each option.
  • You can expend 1 additional mana so no sound can be created within the sphere. Any creature or object entirely inside the sphere is immune to concussion damage, creatures are deafened while entirely inside the sphere, and casting a spell that requires words to be spoken is impossible inside the sphere.

  • You can expend 1 additional mana to cast the spell centered on a point within 20 meters.

  • You can expend 1 additional mana to change the duration to 5 minutes/mana.