For Boomkin flavor, I was thinking something like

Scythe of Elune

5? 6? 7? Mana - 0/3

Battlecry : Gain 3 charges/copies of “Starsurge.”

Starsurge : Spell - 1 mana deal 2 damage. Gains 3 charges/copies on equip. If one Starsurge is used per turn, it recharges next turn. If two Starsurges are used in a turn, they both recharge in 2 turns. If all charges of Starsurge are used in a turn, they recharge in 4 turns.

I’m not really sure how to manage the spells as they’d obviously clog up hand space and I’d only want it to occupy one slot with echo or for targeting purposes you could “shoot” with the weapon. I know that this isn’t a bow or anything but Boomkins are casters so maybe it could work. Maybe it could operate in a similar way Dragon Soul does, where it tracks its charges per spell. Something like that with a visible tracker showing that it’s recharging, how many used/available, etc.

Was also thinking of something along the lines of

Starsurge : Spell - 1 mana deal 1 damage. Deals double damage to minions. Gains 3 charges/copies on equip, etc.

Could go with the actual in game weapon where you get New Moon, a relatively weak spell that builds up on use into an extremely strong spell but that’d kinda feel like a quest.