Multiattack. The captain makes three melee attacks: two with its scimitar and one with its dagger. Or the captain makes two ranged attacks with its daggers. Additionally the sentient tentacle can make a single attack on top of the other attacks, if the sentient tentacle already has an opponent grappled it can constrict.

Scimitar. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 4) slashing damage.

Dagger. Melee or Ranged Weapon Attack: +5 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 5 (1d4 + 4) piercing damage.

Cone of Slime : Once per day as a standard action, a voidmind creature can expel the psionically charged slime in its head in a 30-foot cone. This attack deals 5d6 acid damage. A successful Dexterity save DC 15 for halves the damage. In addition, any creature that takes damage from the spray must make a Wisdom save DC 15 or be stunned for 1d4+1 rounds, save to negate at the end of each of the creatures subsequent turns.

Sentient Tentacle : +5 to hit, reach 5 ft., one target. Hit (1d6+4). On a successful hit the target is grappled. 

Constrict: When the sentient tentacle starts the round with an opponent already grappled it can constrict the opponent dealing (2d6+4) damage.

Parry. The captain adds 2 to its AC against one melee attack that would hit it. To do so, the captain must see the attacker and be wielding a melee weapon.

Alert. Always on the lookout for danger, you gain the following benefits:

• You gain a +5 bonus to initiative.
• You can't be surprised while you are conscious.
• Other creatures don’t gain advantage on attack rolls against you as a result of being unseen by you.