Giant Beetle Diving Larva

This man-sized insect larva is long and thin with enormous mandibles.

Originally Posted by Shade of the En World forums.  
On this Thread  

In its larval stage, the giant diving beetle is ferocious. They are often called ‘water tigers’ both for their coloration and their ferocity.

Larvae prey mostly on snails, small fish, and worms. Over the next several months, they molt three or four times in shallow water, where access to air is easy. Giant diving beetles breathe by trapping air in their bodies, and need only stick the hindmost tip of their abdomens above the surface of the water to replenish their air supply.

In late summer or early fall, the larva digs a burrow for itself underwater, fills it with air bubbles it brings from the surface, and seals itself in. Safe in its earth-cocoon, it pupates-growing into a fat, white, grub-like creature with legs. The pupa is an intermediate form, for soon after it metamorphosizes again, this time into its adult form. At that point it leaves its burrow and rejoins the aquatic environment.

A typical giant diving beetle larvae is 5 to 6 feet in length. Giant diving beetle larvae are translucent when they hatch and gradually become light yellow or orange.

Beetle,Giant, Diving, Larva
Medium vermin (Aquatic)
Hit Dice	2d8+4 (13 hp)
Initiative	+0
Speed	20 ft. (4 squares), Swim 20 ft.
Armor Class	15 (+5 natural), touch 10, flat-footed 15
Base Attack/Grapple	+1/+2
Attack	Bite+2 melee (1d8+1 plus 1d6 acid)
Full Attack	Bite +2 melee (1d8+1 plus 1d6 acid)
Space/Reach	5 ft./5 ft.
Special Attacks	Acid, improved grab
Special Qualities	Darkvision 60 ft., jet, vermin traits
Saves	Fort +4, Ref +3, Will +0
Abilities	Strength 13, Dexterity 10, Constitution 14, Intelligence —, Wisdom 10, Charisma 9
Skills	Hide +4, Swim +9
Feats	–
Environment	Temperate and warm aquatic
Organization	Solitary or cluster (2-12)
Challenge Rating	1
Treasure	None
Alignment	Always neutral
Advancement	3-4 HD (Medium); 5-6 HD (Large)
Level Adjustment	–

COMBAT

They remain motionless against a clump of reeds or other plant stalks, then pounce upon any prey that comes near. Once a larva has a victim in its mandibles, it hangs on until the prey dies or escapes.

Jet (Ex): A giant diving beetle larvae can jet backward once per round as a full-round action, at a speed of 150 feet. It must move in a straight line, but does not provoke attacks of opportunity while jetting.

Skills: A giant diving beetle larvae has a +4 racial bonus on Hide checks. A giant diving beetle larvae has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.

Originally appeared in Dragon Magazine #250 (1998).