Requires Spell Sniper, Potent Specialty or Martial Casting Feats

You have developed a magical affinity with weapons. You gain
the following features.
• By spending 10 minutes mystically attuning to a simple
or martial weapon or a shield, you can use it as an arcane
focus, druidic focus, or holy symbol. This does not count
against the number of magic items to which you can attune.
• You can add bonus damage to one damage roll of a cantrip
you cast. This bonus is equal to the number of magic items
to which you are currently attuned (maximum of +3).
• When you deal acid, cold, fire, lightning, necrotic, poison,
radiant, or thunder damage with a spell while holding a
weapon to which you are attuned, the next time you deal
damage with that weapon before the end of your next turn,
you deal an additional 1d4 damage of that type.