Amphibious. The topaz dragon can breathe air and water. 

Innate Spellcasting (Psionics). The young topaz dragon's innate spellcasting ability is Intelligence. The young topaz dragon can innately cast the following spells, requiring no material components:

At will: feather fall

Multi attack. The young topaz dragon makes two claw attacks and a bite attack

Bite. Melee Weapon Attack: +2 to hit, reach 5 ft., 1 target. Hit: 4 (1d8) piercing damage. 

Claw. Melee Weapon Attack: +2 to hit, reach 5 ft., 1 target. Hit: 2 (1d4) slashing damage. 

Dehydration breath (Recharges on 5/6). The topaz dragon exhales a blast of a watery substance in a 30ft cone. Each creature within range must make a DC 10 Constitution saving throw or the creature gains a level of exhaustion. This breath also can also destroy 8 cubic feet of water.