The pool of cards ("The Cube") consists of all of the best cards in Magic, so when you open your pack, it looks something like this: In the Cube, every pack will contain limited bombs, constructed powerhouses, some old school classics, and some new school brokenness
Galadhrim Ambush Galadhrim Ambush is a very similar card to Arachnogenesis, and it'll probably be a green staple in EDH, particularly in elf decks
You could also use them together for just one more mana then the flashback to kill a bigger body, such as Arrogant Wurm
Turntimber Symbiosis is the best sort of card a tribal player such as myself could hope for from a set which doesnt include your prefered tribe as a theme
Its the best kind of card
Her abilities can freeze opponents in their tracks, giving you the upper hand in critical moments