Karoo actually lets you produce more mana with the same number of lands by returning one of your Plains to your hand, and lands like Buried Ruin can help retrieve a mana rock or another key artifact lost early in the game
Some instant-speed spells, like the Swift End half of Murderous Rider, can destroy creatures or Planeswalkers
If a permanent or player has more than one kind of counter on them, and you choose for that permanent or player to get additional counters, that permanent or player must get one of each kind of counter they already have
Nissa planeswalkers have a very cohesive mechanical identity built around lands, which youd expect from an elf with green magic
Sadly, Twilight Diviner does have a pesky once-per-turn clause
(To earthbend 3, target land you control becomes a 0/0 land creature with haste