We recently had a situation at our table where we had to chase down a mob of Goblins. One of the clerics had cast Spiritual Weapon and found quickly that it was not very helpful as the spectral weapon created can only move up to 20 feet. He kept moving it towards where the battle was going on, but never caught up with the party and it was a waste of a spell.
The spell states: As a bonus action on your turn, you can move the weapon up to 20 feet and repeat the attack against a creature within 5 feet of it. (Player's Handbook, p.278)
Is there any way to increase the speed of Spiritual Weapon by RAW?
I'm looking for an answer that might include feats, multi-classing or a magic item.