Arctic Fox

Keen Hearing and Smell.  The Fox has advantage on Wisdom (perception) checks that rely on hearing or smell.

Spellcasting. The Fox is a 1st-level spellcaster. Its spellcasting ability is Wisdom (spell save DC 13, +5 to hit with spell attacks). The Fox has the following Wizard spells prepared:
Cantrips (at will): Frostbite, Ray of Frost,  
1st level (3 slots): Jump, Longstrider 

2nd level (1 slot): Invisibility

Bite. Melee Weapon Attack: +2 to hit, reach 5 ft., one target. Hit: 7 (2d4 + 2) piercing damage. If the target is a creature, it must succeed on a DC 11 Strength saving throw or be knocked prone.

Action Melee Attack. Melee Weapon Attack: +2 to hit, reach 5 ft., 1 target. Hit: 7 (2d4 + 2) piercing damage. 

Frostbite

Casting Time:

1 action

Range/Area:

60ft.

Components:

V, S

Duration:

Instantaneous

Attack/Save:

CON

Source:

EE, pg. 156

You cause numbing frost to form on one creature that you can see within range. The target must make a Constitution saving throw. On a failed save, the target takes 1d6 cold damage, and it has disadvantage on the next weapon attack roll it makes before the end of its next turn.

Ray of Frost

Casting Time:

1 action

Range/Area:

60ft.

Components:

V, S

Duration:

Instantaneous

Source:

PHB, pg. 271

A frigid beam of blue-white light streaks toward a creature within range. Make a ranged spell attack against the target. On a hit, it takes 1d8 cold damage, and its speed is reduced by 10 feet until the start of your next turn.

Jump

Casting Time:

1 action

Range/Area:

Touch

Components:

V, S, M(a grasshopper's hind leg)

Duration:

1 minute

Source:

PHB, pg. 254

You touch a creature. The creature's jump distance is tripled until the spell ends.

Longstrider

Casting Time:

1 action

Range/Area:

Touch

Components:

V, S, M(a pinch of dirt)

Duration:

1 hour

Source:

PHB, pg. 256

You touch a creature. The target’s speed increases by 10 feet until the spell ends.

Invisibility

Casting Time:

1 action

Range/Area:

Touch

Duration:

Concentration, up to 1 hour

Source:

PHB, pg. 254

A creature you touch becomes invisible until the spell ends. Anything the target is wearing or carrying is invisible as long as it is on the target's person. The spell ends for a target that attacks or casts a spell.

Invisible Cold Companion (Costs 0 Action).

While invisible, if the Fox is within 5ft of an enemy it gives an additional cold damage dice and sneak attack cold damage dice to the Companions Controllers attack damage rolls. 

Starting at 3rd Level.

Additional Sneak Attack Damage: 1d6 Cold Damage

Additional Attack Damage: 1d4

Add an additional damage dice to the extra damage every two levels

(Level 5 is 2d6 Sneak/ 2d4 Attack Damage, Level 7: 3d6 Sneak/ 3d4 Attack Damage...etc)

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