Prereleases are great because the set is totally new, the footing is fairly equal as everybody plays with the set for the very first time, and you're all just relaxing and having fun exploring the new cards
Since starting this list we have an Eldrazi Boar spoiled that also looks set to take a seat in this top ten
Narset at times finds herself torn between her clan and her voracious desire for knowledge, but for now, she has set aside her pursuit and resolved to guide Tarkir toward a better future
Seedglaive Mentor One generic, one red, one white creature Mouse Soldier 3/2 Uncommon Vigilance, haste Valiant Whenever Seedglaive Mentor becomes the target of a spell or ability you control for the first time each turn, put a +1/+1 counter on it
Maybe something a little more sensible is the typical Craterhoof Behemoth or cards of that ilk
The good news is, that ability is good on lots of board states