Magic Resistance. Yojimbo has advantage on saving throws against spells and spell like effects. 

Reactive. Yojimbo can make one reaction per turn. 

Chilling Mist. While it is alive, Yojimbo projects an aura of cold mist within 10 feet of itself. If Yojimbo deals damage to a target in this area, the target also takes 5 (1d8) cold damage (included in the attack).

Deadly Critical. Yojimbo scores a critical hit on a roll of 19 or 20 and rolls the damage dice three times instead of twice.

Unarmored Defense. While Yojimbo is wearing no armor and wielding no shield, its AC includes its Wisdom modifier.

Unarmored Movement. While Yojimbo is wearing no armor and wielding no shield, its walking speed increases by 10 feet (included in its speed).

Multiattack. Yojimbo makes four katana attacks

Katana. Melee Weapon Attack: +11 to hit, reach 5 ft., one target. Hit: 14 (2d8+5) slashing damage, or 16 (2d10+5) slashing damage if used with 2 hands plus 5 (1d8) cold damage. 

Gill Toss (3/day).  Yojimbo casts Animate Objects at 9th level using 20 coins from its pouch. 

Fiendish Spikes (Recharge 5-6). Yojimbo stabs its katana into the ground and causes necrotic spikes to rise from the ground. Each creature it chooses within 30 ft. of Yojimbo must succeed on a DC 20 Dexterity saving throw or take 55 (10d10) necrotic damage, half as much on a successful save. This area is difficult terrain until the start of Yojimbo's next turn. Yojimbo ignores this difficult terrain.

Parry. Yojimbo adds 5 to its AC against one melee or ranged weapon attack that would hit it. To do so, Yojimbo must see the attacker.

Yojimbo can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Yojimbo regains spent legendary actions at the start of its turn.

Move. Yojimbo moves half its speed. This movement does not provoke opportunity attacks. 

Swift Strike (2 actions). Yojimbo makes a Katana attack at advantage. 

Gill Toss (3 actions). Yojimbo uses Gill Toss. This counts as one of his daily uses of the ability.