Expanded Spells:
1st - Zephyr Strike, Inflict Wounds
2nd - Spiritual Weapon, Invisibility
3rd - Haste, Spirit Shroud
4th - Fire Shield, Polymorph
5th - Flame Strike, Destructive Wave

1st level: Engineered Hide
Your pact bestows the knowledge of weapon mastery to you, and enhances your physical form with thicker hide or scales. While you are not wearing armor or holding a shield, your AC equals 13 plus your dexterity modifier. You also gain proficiency in martial weapons and shields.

1st level: Aspect of Perfection
Your senses are enhanced, and you have advantage on Perception checks that rely on hearing or sight.

Your patron offers you two paths: one of adaptability and one of stability. You pick the path of the Canid or the Archosaurian. This choice grants you multiple other unique features throughout this subclass, and cannot be changed.

The Canid. When you take damage from a spell, attack, or other effect that isnt bludgeoning, slashing, or piercing damage, you can use your reaction to gain resistance to that damage type for the next hour. You can use this reaction a number of times equal to your proficiency bonus and regain all uses on a long rest. While you have resistance to that damage type, you deal an extra 1d6 damage of that damage whenever you hit a creature with an attack. You may only have one resistance at a time this way, the oldest ending when you gain a new one. This maximum increases to 2 resistances at 6th level, and 3 at 10th level. When you have multiple resistances active, you only gain the additional damage of the most recent one.

While below half your maximum HP, your speed increases by 10 ft, and may use your charisma mod in place of your strength and dexterity for Acrobatics and Athletics checks.

The Archosaurian. When you hit a creature with an attack, you can attempt to knock that creature prone. They must make a STR save against your spell save DC, falling prone on a fail. You can use this feature a number of times equal to your charisma modifier, regaining all uses on a short rest. While the creature is prone this way, you may use your bonus action on your turn to make a single attack using a weapon or cantrip against only that creature.

You also have advantage on saving throws against the charmed and frightened conditions.

6th level: Primal Enhancement
You’ve grown more accustomed to your new form, learning and adapting its abilities. For the Canid, you’ve learned retaliation, and teamwork. For the Archosaurian, you’ve added power to your strikes, slaying your foes.
 
The Canid. When you attack a creature and one of your allies is within 5 ft of that target, you may grant yourself advantage on that attack roll. If a creature targets you with a weapon attack, you may use your reaction to end the effects of one of your resistances granted by your Aspect of Evolution feature and make a single weapon or spell attack against that creature. On a hit, the creature takes an extra amount of the damage type of the ended resistance equal to your level.

In addition, at the end of a long rest, you can give yourself immunity to one condition of the following: paralyze, charmed, frightened, petrified, blinded, deafened, poisoned, or stunned. This immunity lasts until your next long rest.

The Archosaurian. You may use your CHA mod instead of your STR mod for attack and damage rolls for melee weapons without the finesse property. You cannot be moved against your will, and your speed cannot be reduced by less than half unless you are paralyzed, petrified or unconscious. While grappled, you can still move up to your speed. When you hit a creature with a weapon attack, you can grapple as a part of that attack.

10th level: Inhuman Nature
You’ve gained a heightened awareness, with quicker response time and a physical form that has overcome the barriers of mortality. You gain a second reaction, which must be used on a turn other than the one where you use your normal reaction. Your creature type also becomes Monstrosity, and you grow 4d4 inches taller.

14th level: Monstrous Transformation 
Your pact has granted you the ability to ascend to a higher level of being. As a bonus action, you can choose to take on a hybrid, lycan-like form. This form resembles the creature you chose from first level and lasts for the next ten minutes. You can use this feature once per long rest.

The Canid. Your speed increases by 10 ft. Armor does not impose disadvantage on your stealth checks, and your long jump distance increases to twice your walking speed, and expends half the movement it normally would. At the start of each of your turns when you have at least 1 hit point but fewer hit points than half your hit point maximum, you gain hit points equal to 1 + your Constitution modifier (minimum of 1). If you do not have the thirsting blade feature, you gain an extra attack you can make as part of the attack action on your turn. This attack can also be substituted by casting a cantrip.

When you hit a creature with a weapon attack, you may also force it to make a CON save against your spell save DC. On a fail, the next attack against that creature becomes a critical hit. After a save against this feature fails, you cannot use it again until you next transform

The Archosaurian. You have a +2 to AC while not wearing heavy armor and a +2 to attack and damage rolls made with melee or thrown weapons. You also have resistance to bludgeoning, piercing, and slashing damage from nonmagical attacks not made with silvered weapons. If you do not have the thirsting blade feature, you gain an extra attack you can make as part of the attack action on your turn. This attack can also be substituted by casting a cantrip.

When a creature ends its turn within 5 ft of you, you can use a reaction to make an attack against that creature. On a hit, it must make a STR save against your spell save DC or be knocked prone.