Zardnaar
Legend
The really weird thing is that this druid cantrip was designed to account for multi-classing at all, when multi-classing isn't even assumed in the basic game. Unless you add in that option, the only point of the cantrip is that it lets your druid use a (thematically-appropriate) club or staff for their rare melee attacks, rather than the (technically-allowed) scimitar.
If you're playing in a game that doesn't add the multi-classing options, I would strongly recommend editing shillelagh to have wording more similar to booming blade, so that a high-level druid might actually want to use it.
Its not just MCing though, see previous comment about being able to get it via feats, Tomelocks, Bards, Nature clerics, 3pp via races as well although you can do that with the Vuman as well.