Likely better than Sol Ring, certainly close
It literally lives in the freaking mountains
(Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.) Legendary Creature - Human Rogue Lulu, Loyal Hollyphant Flying At the beginning of your end step, if a permanent you controlled left the battlefield this turn, put a +1/+1 counter on each tapped creature you control, then untap them
If you do, search your library for a planeswalker card, reveal it, put it into your hand, then shuffle
Blood Artist will trigger any time any creature dies, not just your own
Entering as a copy of any creature card from any graveyard, its flexible, reactive, and full of surprises