Spell Selection in Combat: What to Cast and When

Casters have limited slots per day. Spell selection in combat matters.

Here's how to think about it.

Pre-Combat (If You Can)

Buff:

• Bless (Cleric, Paladin): +1d4 attacks/saves for 3 allies.
• Mage Armor (Wizard, Sorcerer): +AC. 8 hours.
• Aid (Cleric): +5 max HP per ally. 8 hours.
• Find Familiar: Free scout/Help.
• Mirror Image (Wizard, Sorcerer): Defensive duplicates.

Pre-cast before fights you anticipate.

Opening (Round 1)

Options

• Concentration buff. Bless, Hunter's Mark, Hex. Sets damage for the rest of the fight.
• Control spell. Hypnotic Pattern, Hold Person, Web. Try to end the fight now.
• Damage nova. Fireball, Scorching Ray. Soften multiple targets.

Which to Pick

• Multiple enemies: AOE damage (Fireball).
• One strong boss: Control (Hold Person, Banishment).
• Long fight expected: Concentration buff (Bless, Hunter's Mark).

Mid-Fight

Maintain Concentration

If you have a concentration spell up, protect it. Don't cast another concentration spell.

React to Threats

• Enemy spellcaster casting big spell: Counterspell.
• Enemy aimed at squishy ally: Shield (on self if target).
• Enemy about to hit you: Shield (if a Wizard/Sorcerer).

Pivot When Needed

If your concentration spell is broken:

• Cast another concentration spell if available.
• Shift to non-concentration damage (Spiritual Weapon, Eldritch Blast).

Emergency Casts

HP Crisis

• Healing Word on self as bonus action.
• Cure Wounds if you have action.
• Potion of Healing (consumable, action).

About to Die

• Misty Step away.
• Dimension Door further away.
• Polymorph yourself into a beast for a new HP pool.

No Options Left

• Use cantrips for consistent damage.
• Dash or retreat.

Slot Management

• Never cast your last 3rd-level slot in a trivial fight.
• Save 2+ slots for the boss.
• Use cantrips when possible.

In The Endlessness

Our AI Dungeon Master tracks your spells and slots. When you cast, the system deducts.

For related reads, our spell slots guide, concentration rules, and best damage spells cover more.

Final Takeaway

Spells are scarce. Pick carefully. Save slots for boss fights. Use cantrips when fights don't demand bigger responses.

Start a caster at The Endlessness and practice spell economy.