As a ranger, you have a strong connection to nature. As a Frost Walker, your love of nature extends to harsh environments aka the arctic. Rangers of the Frost Walker commit to dangerous journeys to connect to the elemental plane FrostFell. Rangers draw magic from FrostFell which unlocks cold related abilities and powerful magic.

For DMs

If you believe this is too powerful then you can always lighten the abilities or the ones of the ranger itself. For example, you can change ice knife for Armor of Agathys, or Sleet Storm for Spirit Shroud (cold only). Also, you could not allow the extra attack option in the ranger rules.

Frost Walker Spells

You gain the following spells which are ranger spells for you but don't count against the spells you know.

Level	Spells
1st	Ice Knife
5th	Snilloc's Snowball Swarm
9th	Sleet Storm
13th	Ice Storm
17th	Cone of Cold

 

Outlandish Form

Due to your exploration with tough conditions you have changed to suit those conditions.

At 3rd level you may choose one of the following options. 

Arctic Explorer

At 3rd level, you may gain a better sense of the environment. You gain another Natural Explorer environment (the arctic) which doesn't count against the number of favoured terrains you have.

Frozen Protection

Whenever you go into combat, you may grant yourself temporary hit points equal to 2 at 3rd level, 4 at 8th level, and 6 at 16th level.

Tough as Nails

While unarmed, you may add 2 to your attack roll.

Winter Warrior

You may add your wisdom modifier to any constitution saving throw.

Hostile Actions

At 7th level, you gain a number of actions you may use. Using one action expends one charge and you regain all charges once you finish a long rest. You have charges equal to your Wisdom modifier (minimum of 1 charge). When you use one charge, you roll on the Hostile Actions table to determine what happens. Some rolls have a level requirement, if so, you must be at that level to use it. Once one action is in effect, you may not use any charges to use the table (unless you summoned a creature) and you may not cast any spells. If you roll one with a requirement that you are not, then you roll again. Explanations for the roll are down below.

Notice. If you summon a creature, you may not summon any other monster. Instead, you roll again.

d100	Outcome
1,33	Storm’s Coming
2-8	(9th level) Cold Burn
9-15	Cold Cat
16-22	Frost Burst
23-29	(9th level) Blizzard Warlord
35-41	1d4 Bewitched Snowballs
42-48	(9th level) Cold Snap
49-55	(9th level) Winter’s Hound
56-62	Defrost
63-69	Armor of FrostFell
70-76	Blade of Winter
77-88	1x Bewitched Snowball
89-99	Icicle Wall
30,31,32,34	Blue 30s
00	(9th level) Flurry of Bewitched Snowballs

A Bewitched Snowball

You create a magical snowball that guids towards the target.

A snowball appears in your hand which you must attack with. Make a ranged weapon attack against a target (range, 30/60ft) ; you are proficient with the attack. You also make the attack with advantage as it magically follows the creature/object you aim it at. On a hit, it deals 1d4 bludgeoning damage and 2d8 cold damage. On a miss, the snowball curves around and deals 1d4 bludgeoning damge and 3d4 cold damage to you.

Armor of Frostfell

You cast the spell Mage Armor without using a spell slot but as if using one of second level.

Blade of Winter

Using your action, you magically enchant any sword; conjuring a Blade of Winter. Whenever you attack with that weapon, it deals an extra 3d6 cold damage as well as it's normal damage. You may use this feature a number of times equal to 2 plus your wisdom modifier.

Blizzard Warlord

You gain immunity to cold damage and you gain darkvision of 100ft. The darkvision lasts for 30mins and the damage immunity lasts for 3 rounds.

Blue 30s

You change the emotional state of the group. All creatures within a 60ft radius start bawling their eyes out. They cry out calling "MUMMY!!" at random intervals and squeal like pigs. This lasts for a random duration. Roll a d100, an even number means it's 30mins long and an odd number means it's 1hour and 30mins long.

Cold Burn

Choose a spell you gained in this archetype and cast it (must deal damage). The cold damage it deals, becomes the hightest possible outcome, for example, a spell dealing 3d8 cold damage would deal 24 cold damage.

Cold Cat

You summon a Crag Cat which acts as a follower and friend. It will attack with you for one session of combat and then will remain with you. If you roll this option again, the Crag Cat will attack for you for another session. You may add your proficiency bonus to all of its attacks and attack rolls. The Crag Cat magically suffers no penalty against all weather conditions and difficult terrain.

Cold Snap

You summon the power of the great arctic, and release all of it apon one creature. As an action, you target one creature of your choice within 30ft of you to make a constitution saving throw against your Spell Save DC. On a successful save, the creature takes 1d8 cold damage. On a failed save, the creature takes 2d8 cold damage and begins to turn to ice. The creatures legs are frozen, making him restrained. As the target's next action, it may then make either a strength saving throw to break out of the ice, or a constitution saving throw to over come the magic and move freely. On a successful save, the creature is free from its ice restraints. On another failed save, the creatures torso is covered, making it also incapacitated. At the start of the creature's next turn, he must make the same saving throw to break free. If not, the creature is paralyzed in ice for one hour.

Defrost

Any creature you can see magically defrosts. As your action, any creature trapped by ice or is frozen magically defrosts in the time of 2 rounds. 

Flurry of Bewitched Snowballs

You create 5 Bewitched Snowballs witch fly around you. As an action, you may use one snowball and attack with it (detailed above). If you have snowballs zooming around you, attack damge suffer a penalty equal to the number of snowballs you still have x2.

Frost Burst

You release built up energy within your body. Any form of water within a 30ft radius freezing instantly. If the temperature is below freezing, the water stays frozen. Otherwise, the water stays frozen for 15mins.

Icicle Wall

You cause shards of ice to fall from the ceiling, stretching until they reach the floor. An icicle can have a size up to 20ft otherwise they stretch to as far as they can go without reaching the floor. One icicle takes up the space of a medium creature. If there is no ceiling, the icicles stretch upward from the ground. The wall has a length of 30ft or, if in a small room, the length between two sides that is less than 30ft. Any creature inside the space when the icicles emerge, takes 1d6 piercing damage and 1d8 cold damage. The icicles last for 30 mins or until they take 30 fire damage.

Storm's Coming

Target one creature you can see, and force it to make a constitution saving throw (against your spell save DC). On a fail, it takes 1d8 thunder damage and 1d8 cold damage as thunderous howls of blizzards threaten to pour down. On a successful save, it takes half as much damage.

Winter's Hound

You summon a Winter Wolf which acts as a follower and friend. It will attack with you for one session of combat and then will remain with you. If you roll this option again, the Winter Wolf will attack for you for another session. You may add your proficiency bonus to all of its attacks and attack rolls. The Winter Wolf magically suffers no penalty against all weather conditions and difficult terrain.

Sense of Frost

Your winter lands senses become heightened allowing you to be aware of things you may not see or hear.

At 11th level, you learn the spell Clairvoyance (targeting ice or frost) which doesn't count against the number of ranger spells you know, and you may cast it without requiring a material component. You may also cast it once without requiring a spell slot which recharges after a long rest.

Frozen Phantom

At 15th level, you may go and pass at will with nothing stopping you.

When moving, if ice, snow or frost blocks your path, you may reduce your form to nothing more than frigid air until the start of your next turn. While in this form, you may pass through the blockage up to your movement speed. You also gain immunity to cold damage and grant disadvantage to any attacker who targets you. You may use this a number of times equal to your proficiency bonus.

In addition, you gain resistance to cold damage and suffer no penalties from arctic environments or weather.