Wyvern

Large dragon, unaligned
Armor Class 13 (natural armor)
Hit Points 110 (13d10 + 39)
Speed 20 ft., fly 80 ft.
STR
19 (+4)
DEX
10 (+0)
CON
16 (+3)
INT
5 (-3)
WIS
12 (+1)
CHA
6 (-2)
Skills Perception +4
Senses darkvision 60 ft., passive Perception 14
Languages -
Challenge 6 (2300 XP)
ACTIONS

Multiattack. The wyvern makes two attacks: one with its bite and one with its stinger. While flying, it can use its claws in place of one other attack.

Bite. Melee Weapon Attack: +7 to hit, reach 10 ft., one creature. Hit: 11 (2d6 + 4) piercing damage.

Claws. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit: 13 (2d8 + 4) slashing damage.

Stinger. Melee Weapon Attack: +7 to hit, reach 10 ft., one creature. Hit: 11 (2d6 + 4) piercing damage. The target must make a DC 15 Constitution saving throw, taking 24 (7d6) poison damage on a failed save, or half as much damage on a successful one.

Cousins to the great dragons, wyverns have two scaly legs, leathery wings, and a sinewy tail topped with a poison stinger that can kill a creature in seconds.
Monster Manual (SRD) D&D 5 › Monsters