Beamos (5e Creature)
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Large construct, unaligned
Saving Throws Con +7
Antimagic Susceptibility. The beamos is incapacitated while in the area of an antimagic field. If targeted by dispel magic, the beamos must succeed on a Constitution saving throw against the caster's spell save DC or fall unconscious for 1 minute.
Immutable Form. The beamos is immune to any spell or effect that would alter its form.
Weak Point. An attack which specifically targets the beamos's eye-gem bypasses its damage resistance. If the attack inflicts piercing damage, it not only bypasses immunity and resistance, but inflicts double damage. Any attack roll made as a called shot, such as against this weak point, is normally made with disadvantage.
Eye Beam (Recharge 2-6). The beamos produces a line of concentrated energy beam that is 120 feet long and 5 feet wide. Each creature in that line must make a DC 15 Dexterity saving throw, taking 38 (11d6) radiant damage on a failed save, or half as much damage on a successful one.
Beamos are ancient constructs which guard temples and dungeons alike from intruders. They appear as tall, rotating machines with a single red gem perched at their tops. They attack with powerful energy rays from their eye-like gem. One of their more exploitable weaknesses is that they have a very limited vision-range, so long-ranged attacks will work wonders against them.