The objective of this deck is to ramp up so you can play Guardian Animals and pull some beasts as fast as possible on early matches. On later matches you can play Alexstrasza on the enemy hero and burst him down with spells next turn.

In general you're looking for cards like spells that deal damage, mana reduction spells, ramp spells, beasts, and sustain cards.

For passive treasures in the first pool you're looking for spell mana reduction ones like [Rhonin's Scrying Orb] or [Robe of Shrinking], or even [Sticky Fingers].

For the second pool [Double Time] is ideal, since it allows your first spell to be casted twice; so you ramp up double as fast, get some value out of cards like Nature Studies for value, or even cast damage spells like Swipe twice. [Robe of the Magi], [Scepter of Summoning], [Emerald Goggles], and [Khadgar's Scrying Orb] are also good.

For active treasures there's a lot of good ones that can synergize with this deck, check up the link below to see them.

You can look up the different treasures here: https://hearthstone.gamepedia.com/Duels since this site doesn't have these cards yet (I think).