D&D 5E Dragon Slaying in 5e

[Derren]

Step one is to ensure the dragon you're fighting has a CR less than or equal to your party level.

There are enough reports of unoptimized parties beating dragons with way higher CR than their level.

 

[Authweight]

What I've found in my limited experience with 5e dragons is that their breath attack is extremely powerful. If the dragon is able to use hit and run tactics with its breath weapon, then the party may be in trouble. Parties should either plan on doing most of their damage at range, using some spell or ability to force the dragon to land and fight, or engaging the dragon somewhere that hit and run will be ineffective.