Large robot

Armour Class 18 (heavy body, 4 heavy plate)
Hit Points 210 (20d10 + 100)
Speed 50 ft.

18 (+4) 14 (+2) 20 (+5) 10 (+0) 13 (+1) 12 (+1)

Skills Intimidation +8, Perception +8
Damage Immunities Poison, Radiation
Condition Immunities Frightened, Poisoned, Radiation Sickness
Senses passive Perception 18
Languages American English
Challenge 15 (13,000 XP)

Machine. The sentrybot is immune to poison, radiation and all forms of disease. It does not need to eat or sleep, but enters an inactive state for at least 4 hours a day to conserve power. The sentrybot cannot use stimpaks or other items intended for biological creatures.

Nuclear Blast. When reduced to 0 hit points, the sentrybot explodes with the force of a mini-nuke. The explosion affects a 45-foot radius circle centered on the sentrybot. All creatures within the affected area must make a DC 15 Dexterity saving throw. The damage dealt to a creature depends on where it is relative to the explosion’s ground zero, as shown in the table below. On a successful save, a creatures takes only half the listed damage.

Ground Zero 9d12 fire and 91d12 radiation
10 ft. 7d12 fire and 71d12 radiation
20 ft. 5d12 fire and 51d12 radiation
30 ft. 3d12 fire and 31d12 radiation
40 ft. 1d12 fire and 11d12 radiation


Multiattack. The sentrybot makes one attack with its minigun and one attack with its missile launcher.

5.56mm Minigun. The sentrybot can pepper a 10-foot cube area within 240 feet with shots. Each creature in the targeted area must succeed on a DC 15 Dexterity saving throw (with advantage if they are more than 80 feet from the Sentrybot) or take 22 (8d4 + 2) piercing damage.

Missile Launcher. Ranged weapon attack: +7 to hit, range 100/300 ft. Special: The sentrybot chooses any target within range and makes an attack roll against a DC of 10, or 15 if the target is in long range. If the sentrybot fires at a target behind cover, apply the cover bonus that usually applies to a target’s AC to the DC.

If the attack roll is lower than the DC, the missile lands 5 feet away from the original target for every 1 by which the sentrybot’s result fell short, in a randomly determined direction (assign compass directions to a d8).

All creatures within 15 feet of the point of impact must make a DC 15 Dexterity saving throw. On a failed saving throw, a creature takes 35 (10d6) fire damage, or half that on a success.

Fallout is the sole intellectual property of Bethesda Softworks. This is purely a fan work. Rules presented work with D&D 5e. Text and game mechanics presented in this wiki are not Open Game Content and should not be reproduced or repackaged in any way.