You gain ancient insights into the circle of life and death, and become privy to certain druidic mysteries. Collected here is the Pact of the Harvest and various Eldritch Invocations that require it as a prerequisite.
You gain proficiency with Two-handed Scythes (treat as a Halberd) and Scimitars, if you do not already have it. In addition, you gain Weapon Mastery with your choice of Sickle, Scimitar, or Halberd and you may switch your choice of mastery between these three options when you finish a Long Rest.
Druidic. Your patron grants you knowledge of Druidic, the secret language of Druids. You can speak the language and use it to leave hidden messages. You and others who know this language automatically spot such a message. Others spot the message's presence with a successful DC 15 Intelligence (Investigation) check but can't decipher it without magic.
Cantrips. Finally, your patron grants you Druidcraft and a cantrip of your choice from the Druid spell list as free cantrips that do not count against your limit and are Warlock spells for you.
Prerequisite: Level 3+ Warlock, Pact of the Harvest
As an action you may attempt to beguile any number of Blight creatures within 150 feet that have a combined challenge rating of up to half your Warlock level (rounded down). Each affected creature must succeed on a Wisdom saving throw. Any that fail their saving throw are charmed by you for a duration of Concentration, 4 hours. If you or your allies harm a Blight charmed in this way, the effect ends on that creature immediately.
You have a telepathic link with all of the currently charmed Blights while you remain on the same plane of existence, and both you and they can sense the general direction and distance towards each other. You can use this telepathic link to issue a command as a Bonus Action to one or more of the charmed Blights. You can specify a simple and general course of action, such as 'Kill that creature,' 'Run over there,' 'Come to me,' or 'Bring me that object.' If a charmed Blight completes the last order given, it will defend and preserve itself to the best of its ability while it remains charmed, until it receives another order from you.
Prerequisite: Level 3+ Warlock, Pact of the Harvest
Choose a spell from the Druid spell list of a level you can cast using your Pact Magic. While you have this invocation, you have the chosen spell prepared and it functions as a Warlock spell for you. You can also cast the chosen spell once per Long Rest without expending a spell slot.
Repeatable. You can gain this invocation more than once, but must choose a spell you do not know from the Druid spell list each time.
Prerequisite: Level 5+ Warlock, Pact of the Harvest
You learn a magical rite that allows you to create Blights. To use this rite, you must meditate uninterrupted for 4 hours over a dead plant or tree that is Medium or larger. At the end of this hour you transform the dead plant or tree into your choice of four Twig Blights or two Needle Blights or one Vine Blight. A Blight created by you in this way understands basic Druidic and is charmed by you for 30 days or until you or your companions do anything harmful to it. When the charmed condition ends, each Blight chooses whether to remain friendly to you, based on how you and your allies treated it while it was charmed.
Once you use this invocation you must finish a Long Rest before you can use it again.
Prerequisite: Level 5+ Warlock, Pact of the Harvest
When you cast a spell using a spell slot that deals Necrotic damage to one or more creatures other than yourself, you can choose one of the damaged creatures. If you do, select a different creature that you can see within 60 feet to regain a number of Hit Points equal to the amount of Necrotic damage taken by the chosen damaged creature.
Flow and Ebb. Alternatively, when you cast a spell using a spell slot that restores some number of Hit Points to one or more creatures, you can choose one of the healed creatures. If you do, target a different creature that you can see within 60 feet. The target must succeed on a Constitution saving throw or take an amount of Necrotic damage equal to the number of Hit Points regained by the healed creature.
Refreshable. Once you use this invocation you cannot use it again until you finish a Long Rest unless you expend a Pact Magic spell slot (no action required) to restore your use of it.
Prerequisite: Level 5+ Warlock, Pact of the Harvest
As a Bonus Action during your turn you may enchant a Two-handed Scythe (treat as a Halberd) that you are wielding, or conjure a spectral one into your empty hands. The enchantment lasts for 10 minutes unless you are Incapacitated or die, or if the enchanted weapon is separated from you for more than 1 round, any of which end the effect.
Fell Strikes. For the duration, you may use Charisma as your attack attribute when wielding the enchanted weapon and attacks made by you with it deal an extra 1d10 Necrotic damage. When you hit a creature with the enchanted weapon, you regain Hit Points equal to the amount of Necrotic damage that creature takes. When you score a critical hit on a creature with the enchanted weapon, all enemy creatures within 20 feet that can see you must succeed on a Charisma saving throw or gain the Frightened condition for 1d4 rounds.
Refreshable. Once you use this invocation you cannot use it again until you finish a Long Rest unless you expend a Pact Magic spell slot (no action required) to restore your use of it.
Prerequisite: Level 9+ Warlock, Pact of the Harvest
When you take this invocation, if your body is not already tree-like it becomes tree-like, and if your creature type does not already include plant it is changed to include plant. You gain the following benefits:
If you replace this invocation, any changes to your body and / or creature type caused by this invocation are reverted.