There are a lot of spells in Dungeons & Dragons, some of which are very powerful, and some have the potential to actually break the game. Some spells listed in D&D sourcebooks have very clear wording on using them, while others are a little more open-ended. Most of what could be considered game-breaking comes from how the players interpret and use the spells at their disposal.
Game breaking is a subjective term in D&D as what one player or DM might consider game breaking another might have no problem with. Some D&D spells offer up a lot of possibilities to end encounters immediately or temporarily derail campaigns. Certain spells can even break in-game economies; for instance, the ninth level transmutation spell true polymorph has made many DMs cry as players simply create gold for themselves.
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Higher-level spells are designed to have a big impact on gameplay, so for this reason, no ninth-level spells will be included here. Using the spells here could break a D&D game without cheating but would perhaps cause a touch of chaos. None of these D&D spells are particularly overpowered; what makes them game-breaking is the potential mayhem they can unleash in the hands of a very imaginative player.
Phantasmal force is a second-level illusion spell available to Bards, Wizards, and Sorcerers. The target must make an Intelligence saving throw; on a fail, the target will believe whatever illusion the player has invented. The target will see this illusion and be the only one who can, as the spell takes root in the target's mind. The affected target would rationalize any inconsistencies between reality and the illusion. To end the D&D spell, the target must use their action to
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