Adding to a Classes Spell List

[MonkeezOnFire]

Magic items would be a good way to go about doing this. The Wand of Lightning Bolts was already mentioned but you can really put any spell into a wand or any collection of spells into a staff and then give it an appropriate rarity based on the level of spells. The DMG encourages magic item creation of this kind event.

Also because many of the tempest cleric abilities key off of "when you roll lightning damage" and not from casting spells that deal lightning damage a Staff of Thunder and Lightning would be a very attractive weapon.

 

[Dausuul]

I would go with re-fluffing the current spells, that way you don't have to think about balancing it too much. Spiritual weapon is not a weapon but it's a small cloud that strikes lightning on command. Spirit guardians are now called Lightning field, where there is a field of electricity around the cleric with the same effect. Healing spells are like little defibrillators when others are down. You can do a lot with a little imagination and you wont have to really change anything.

This is why I grimace when people talk about "re-fluffing." The consequences usually extend a good deal further than they realize. In this case, you just gave spiritual weapon - which is already a powerhouse spell - the ability to knock back its target 10 feet on every hit.

Thunderbolt Strike: At 6th level, when you deal lightning damage to a Large or smaller creature, you can also push it up to 10 feet away from you.

 

[mortwatcher]

This is why I grimace when people talk about "re-fluffing." The consequences usually extend a good deal further than they realize. In this case, you just gave spiritual weapon - which is already a powerhouse spell - the ability to knock back its target 10 feet on every hit.

so? this to me seems of very little consequence/can be talked about with the player (tell them that it is just fluff and will have no mechanical consequence) - like he wanted more sonic attacks, that damage type is "technically" not in the game, doesn't prevent you from re-fluffing stuff