Amorphous Blob

Amorphous Blob

Tiny ooze, unaligned

Armor Class 8

Hit Points 10 (1d10 + 5)

Speed 5 ft., climb 5 ft.

Damage Immunities acid, fire, lightning, bludgeoning and piercing from nonmagical attacks, slashing

Condition Immunities blinded, charmed, deafened, exhaustion, frightened, poisoned, prone

Senses blindsight 60 ft. (blind beyond this radius), Passive Perception 8

Languages —

Challenge — Proficiency Bonus +2

Absorb. At the start of its turn, the blob absorbs any dead creature it has engulfed. When the blob absorbs a dead creature, the creature dissolves, any nonmagical items in the creature's possession are destroyed, and the blob gains a number of Hit Dice (d10s) equal to half the creature’s number of Hit Dice. Roll those dice, add the blob's Constitution modifier to each roll, and increase the blob’s hit points and hit point maximum by the result.

For every 4 Hit Dice the blob has, it gains a +1 bonus to attack rolls, saving throws, and the save DC of its Engulf.

When the blob's current number of Hit Dice equals twice the number of Hit Dice it originally had when it reached its current size, its size increases by one category and its speed increases by 5 feet.

The blob can exceed Gargantuan in size.

Amorphous. The blob can move through a space as narrow as 1 inch wide without squeezing.

Corrosive Form. A creature that touches the blob or hits it with a melee attack while within 5 feet of it takes 3 (1d6) acid damage per size category of the blob. Any nonmagical weapon that hits the blob corrodes. After dealing damage, the weapon takes a permanent and cumulative −1 penalty to damage rolls. If its penalty drops to −5, the weapon is destroyed.

Nonmagical ammunition made of metal or wood that hits the blob is destroyed after dealing damage.

The blob can eat through 2-inch-thick, nonmagical wood or metal in 1 round.

Freeze. If the blob takes cold damage, it partially freezes; its speed is halved until the end of its next turn.

Lightning Absorption. Whenever the blob is subjected to lightning damage, it takes no damage and instead regains a number of hit points equal to the lightning damage dealt.

Ooze Pool. Other creatures can enter the blob's space, but a creature that does so is subjected to the blob's Engulf and has disadvantage on the saving throw.

Creatures inside the blob can be seen but have total cover.

A creature within 5 feet of the blob can take an action to pull a creature or object out of the blob. Doing so requires a successful Strength check against the DC of the blob's Engulf, and the creature making the attempt takes 3 (1d6) acid damage per size category of the blob.

The blob can only hold as many creatures as will fit in its space inside it at a time.

Regeneration. The blob regains 10 hit points at the start of its turn if it has at least 1 hit point. If the blob takes cold damage, this trait doesn't function at the start of the blob's next turn.

Spider Climb. The blob can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Actions

Multiattack. The blob makes two attacks: one with its engulf and one with its pseudopod. For each size category the blob achieves above Tiny, it can make one extra pseudopod attack.

Pseudopod. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 3 (1d6) acid damage per size category of the blob, and if the target is wearing nonmagical armor, its armor is partly corroded and takes a permanent and cumulative −1 penalty to the AC it offers. The armor is destroyed if the penalty reduces its AC to 10.

Engulf. The blob moves up to its speed. While doing so, it can enter a creature’s space if the creature is the same size category as the blob or smaller. Whenever the blob enters a creature's space, the creature must make a DC 12 Dexterity saving throw.

On a successful save, the creature can choose to be pushed 5 feet back or to the side of the blob. A creature that chooses not to be pushed suffers the consequences of a failed saving throw.

On a failed save, the blob enters the creature's space, and the creature takes 3 (1d6) acid damage per size category of the blob and is engulfed. The engulfed creature can't breathe, is restrained, and takes 7 (2d6) acid damage per size category of the blob at the start of each of the blob's turns. Any nonmagical equipment the target is wearing or carrying corrodes as described in the blob's Corrosive Form trait and Pseudopod attack. When the blob moves, the engulfed creature moves with it.

An engulfed creature can try to escape by taking an action to make a DC 12 Strength check. On a success, the creature escapes and enters a space of its choice within 5 feet of the blob. A creature reduced to 0 hit points while engulfed dies and subjected to the blob's Absorb trait.

Reactions

Merge. When two blobs touch, they merge into a single, larger blob. The blob with the higher initiative instantly absorbs the other, gaining its hit points and Hit Dice.