Utopia Sprawl and Elemental Energy are great for pumping up the mana.
Birds of Paradise also helps with ramping, and is great for when one of your colors is not coming up early enough (besides being a mana dork, period).
Terrarion is great to filter mana early.
Seeds of Strength only boosts until end of turn, instead of with +1/+1 counters, yet it's great to pick where the boost goes.
Here is a simple board that left unhindered, will finish the game for the win.
Here is yet another simple board that will do the same.
Being able to Convoke thanks to a good number of creatures is a great combo with Elemental Resonance.
And Selesnya Guildmage can be pumped multiple times (twice in the example below).
