The Warlock: Magic You Borrowed from Something Worse Than You
The warlock is the only class in 5e where the fiction of how you got your magic actually changes how the magic works mechanically. Wizards study. Sorcerers are born with it. Warlocks made a deal, and the rules never let you forget that.
The Spell Slot Problem (That Isn’t Really a Problem)
Pact Magic is the first thing that throws new warlocks off. You have very few spell slots, they cap at 5th level, and they come back on a short rest rather than a long one. What the table doesn’t make obvious is that every spell you cast fires at the highest level available to you. No upcast decisions, no rationing your 3rd level slots against your 1st level slots. You have one tier of slot, and everything you cast uses it. It’s a cleaner system than it looks on paper, and it rewards picking spells that scale well.
The spell slot drought at higher levels is addressed by the Mystic Arcanum, which arrives at 11th level. From that point, your patron essentially hands you one spell per tier, 6th through 9th, that you can cast once per long rest without touching your Pact Magic slots at all. It’s a strange delivery mechanism, but it keeps the flavor intact. You’re not generating magical power from within. You’re drawing on something else, and that something else has limits it chooses to give you.
Pact Boon: The Choice That Shapes Everything
At 3rd level, your patron gives you a gift, and the three options land very differently in practice.
Pact of the Tome gives you three cantrips from any class list. Any class. The versatility here is real, and it’s the default choice for good reason. If you’re not building toward a specific playstyle, this is where you start.
Pact of the Blade creates a magical weapon in your hand on demand. Immune to the “non-magical damage” immunity that shows up constantly at higher tiers, and it vanishes completely when you dismiss it. For a warlock who wants to fight in melee, particularly a Hexblade build, this is the foundation.
Pact of the Chain gives you Find Familiar with expanded form options: imps, pseudodragons, quasits, sprites. The warlock version of the familiar can also receive your touch-range spells as a delivery mechanism, which opens up some genuinely creative plays. The dismissal and resummon mechanic, which lets it reappear within 30 feet without line of sight, is the part most people overlook entirely.
The Level 20 Feature
Eldritch Master lets you spend one minute entreating your patron to recover all expended Pact Magic spell slots, usable once per long rest. It does not affect the Mystic Arcanum. At level 20, doubling your below-5th-level casts per day is fine, but it mostly highlights the gap between the two systems rather than bridging it. It’s a ribbon with mechanical weight, which is a very warlock way to end up.