The combination of searching up a specific card and circumventing its mana cost is the devastating one-two punch on several unfair Magic cards (see Tinker and Stoneforge Mystic)
It gives all your creatures ward 3, which is pretty amazing, and it also turns one creature into a 7/7 and another into a 1/1 whenever it attacks
Delve is used to great effect on a few cards, but more ways to cast huge spells for less while still triggering the higher cost for Rootha is an easy upgrade
1 Green for a 0/2 with flying that creates a Food Token when it enters, creates as many Food Tokens as you like for 2 mana, and allows you to add one mana to your pool if you sacrifice a Food is indeed a great deal
Split cards have both their sides names, their mana value is the sum of both sides mana values, and their colors are the sum of all their sides' colors everywhere other than the stack
Good news/bad news: theres even more very cool cards coming soon