Evasion: If the creature is subjected to an effect that allows it to make a Dexterity saving throw to take only half damage, the creature instead takes no damage if it succeeds on the saving throw, and only half damage if it fails.

Flight: As a bonus action, Xavlans can take flight and maintain flight without consentration

Magic Resistance: The creature has advantage on saving throws against spells and other magical effects. When magical attacks are made against the creature, damage is halved.

Spellcasting. Xavlan is a 2nd level spellcaster. Its spellcasting ability is 15 (spell save DC #, +# to hit with spell attacks). Xavlans have the following spells prepared:
Cantrips (at will): Acid Splash, Viscious Mockery
1st level (3 slots): Inflict Wounds, Magic Missile, Hideous Laughter

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., # target. Hit: 14 (3d6 piercing) damage. 

Poison (Costs 1 Action). Xavlans shoot a bright purple and black line of ooze that stings and burns the skin. Creatures in a 10ft cone (2x2 square on a grid) must make a Con saving throw (DC 17) or they are poisoned: Disadvantages on all attack rolls and ability checks/saves for 2 turns.

Suck (Cost 1 action, must be prepared for 1 turn): Xavlans can prepare one turn, not public knowledge, and then attacks at a creature up to 10ft away and bites them. Melee attack, +6. On a hit, the creature must make a con save (DC 17) or they will take 2d10 necrotic damage. Xavlans cannot use Suck for another 5 turns.