Sources
CR
Type
Size
Alignment
Movement

Caustic Crawler

Large Monstrosity, Unaligned

Armor Class 14 (natural armor), 11 while prone
Hit Points 39 (6d10 + 6)
Speed 30 ft., burrow 10 ft.
STR
17
+3
DEX
11
+0
CON
13
+1
INT
1
-5
WIS
13
+1
CHA
6
-2
Senses darkvision 60 ft., tremorsense 60 ft., passive Perception 11
Languages
Challenge 2 (450 XP)

Actions

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit:10 (2d6 + 3) slashing damage plus 3 (1d6) acid damage. If the target is a Large or smaller creature, it is grappled (escape DC 13). Until this grapple ends, the crawler can bite only the grappled creature and has advantage on attack rolls to do so.

Acid Spray (Recharge). The crawler spits acid in a line that is 30 feet long and 5 feet wide, provided that it has no creature grappled. Each creature in that line must make a DC 13 Dexterity saving throw, taking 10 (3d6) acid damage on a failed save, or half as much damage on a successful one.

Lore

The black mana that brews and festers in Zendikar's swamps infuses a wide variety of natural animals, creating large, deadly vermin—rats, bats, insects, scorpions, and spiders that spread death and decay with their bites, stings, or caustic saliva. The swamps of Guul Draz are home to many such creatures, from the enormous heartstabber mosquitoes (best represented with stirge statistics) to giant scorpions large enough to hold a struggling vampire in one claw. The gigantic, ant-like…