15 Feb Phantasmal Force 5e D&D Guide 
The Phantasmal Force spell is a really fun spell to use for characters who specialize in illusion magic. It can be overlooked for more damage-heavy spells at level 2 but does add a lot of role-play potential for the right player and group.
The rules for Phantasmal Force are found in the Players Handbook on page 264.
Phantasmal Force 5e
Illusion 2nd level
Casting Time: 1 Action
Range: 60 feet
Components: V, S, M (A bit of fleece)
Duration: Concentration,up to 1 minute
You craft an illusion that takes root in the mind of a creature that you can see within range. The target must make an Intelligence saving throw. On a failed save, you create a phantasmal object, creature, or other visible phenomena of your choice that is no larger than a 10-foot cube, and that is perceivable only to the target for the duration. This spell does not affect undead or constructs.
The phantasm may include sound, temperature, and other stimuli, all evident only to the targeted creature.
The target can use its action to examine the phantasm with an Intelligence (Investigation) check against your spell save DC. If the check succeeds, the target realizes that the phantasm is an illusion, and the spell ends.
While a target is affected by the spell, the target treats the phantasm as if it were real. The target rationalizes any illogical outcomes from interacting with the phantasm. For example, a target attempting to walk across a phantasmal bridge that spans a chasm falls once it steps onto the bridge. If the target survives the fall, it still believes that the bridge exists and comes up with some other explanation for its fall;it was pushed, it slipped, or a strong wind might have knocked it off.
An affected target is so convinced of the phantasm’s reality that it can even take damage from the illusion. A phantasm which is created to appear as a creature can attack the target. Similarly, a phantasm created to appear as fire, a pool of acid, or lava can burn the target.
Each round on your turn, the phantasm can deal 1d6 psychic damage to the target if it is in the phantasm’s area or within 5 feet of the phantasm, provided that the illusion is of a creature or hazard that could logically deal damage, such as by attacking. The target perceives the damage as a type appropriate to the illusion.
The rules for Phantasmal Force do a great job of outlining what this spell can and can’t do. They also reveal the lack of up-casting the spell, which indicates that it is more a circumstantial preparation than a regular on the prepared list.The spell save DC does increase with the character, so there are some benefits of keeping it on hand at higher levels.
What classes get Phantasmal Force?
Phantasmal Force is limited to the Bard, Sorcerer, Great Old One Warlock,Archfey Warlock, and Wizard base classes. It is also available to the Eldritch Knight andArcane Trickster sub-classes. Expansion books gave Phantasmal Force to the Genie Warlock as well.
Can Phantasmal Force Restrain?
Phantasmal Force is an illusion. While it can affect a creature to cause physical harm, it can’t actually restrain the creature.Mentally the creature would justify being able to move or defend itself from another source but may not pass the illusion.
For example, a creature affected by Phantasmal Force that sees a spider with webs may believe it is stuck in the webs and doesn’t move. However, when it sees an attack from another source, it can still defend itself.
Can Phantasmal Force Cause the Target to Go Prone?
Similar to attempting to restrain a creature, a physical motion cannot force a creature to go prone. That being said, an image that creates a scenario where the target may go prone is a possibility.The illusion of a slick surface or a lowering ceiling might do the trick.
There are no specifics provided for restraining or forcing a creature prone using Phantasmal Force. This is left up to the DM to interpret. Damage should still be done if the desired condition cannot be met.
What can Phantasmal Force Do?
- Create an illusion of a monster to attack the target
- Create an illusion of something that damages the target, such as fire
- Create an illusion of a dark space in front of the creature blocking its sight
- Create an illusion of a pit causing the enemy to suffer fall damage
Illusion spells can be so much fun to use, and Phantasmal Force is no different. It is a damage-dealing illusion spell that has almost no confines to operate within. The sky is the limit. That being said, it is subjective and will only be as great as the player’s description and the DMs willingness to go along.
Illusion spells add a lot of flavor to the game and can be some of the most creative opportunities in the game.