Once a creature that has reach because of Sphere Grid's last ability has blocked a creature, removing all +1/+1 counters from that creature or causing Sphere Grid to leave the battlefield won't cause that creature to stop blocking
Eriettes Lullaby is a removal spell that does not go into every deck, so I was a little bit hesitant to include it in the top 5, but the gain 2 life did push it over the line for me
This simplicity is why many players still rank Atarka among the best MTG cards for aggressive Commander strategies
Once you know how you want to win the game, you can get started on which cards actually go into it
At three mana, a 2/3 vigilant flyer is a good rate, and her ability is pretty strong
Uno: Chances, How Long Games Last, and Rules Like this, for sample the chance to pull a green card match to the ratio of green cards shared by the whole number of remaining cards