Mana rocks that provide 2 or more mana are a great type of artifact to untap
Obviously you need to be in a combat focused deck for this one, but if you are I see little reason why you wouldn't cram this in if your manabase can warrant a few taplands
Green also has lots of effects that care about creatures, including the best tutors like Worldly Tutor and Green Sun's Zenith and cards that benefit from having creatures like Rishkar's Expertise
I couldnt cover everything, but I got most of whats worth adding to your collection
10 Emet-Selch, Unsundered Can Be A Great Partner For Graveyard Synergy A Powerful Commander Card With Even Greater Combo Potential Although a commander like Emet-Selch, Unsundered and his Hade, Sorcerer of Eld backside is harder to fully utilize in most decks, it still has great potential for some powerful combos, whether he's your primary commander or not
Cant we just play answers that kill Murktide Regent and the other random things we care about