Deadly Gecko (5e Creature)
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Medium beast, unaligned
Chameleon Skin. The gecko has advantage on Dexterity (Stealth) checks made to hide.
Spider Climb. The gecko can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.
Bite. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 8 (1d8 + 4) piercing damage, and the target must make a DC 13 Constitution saving throw, taking 9 (2d8) poison damage on a failed save, or half as much damage on a successful one.
Due to staying in the swamp wherein black or green dragon dwell, these geckos mutated and became filled with deadly toxins. Though their physical characteristics haven't changed much, other than size, they have become defensive creatures, attacking aggressively when provoked. They are large enough to be used as mounts by creatures in the "Small" size category. These Geckos are great at scaling rocky terrain. Their natural colors vary wildly, usually based on their natural environment. Their lengths ranges anywhere from 6 to 10 feet from nose to tail and they typically weigh around 100 to 150 pounds.