Gates lands only added half credit for daily quest to play 40 lands.
For my daily reward I have the quest to play 40 lands.
I chose a gates deck to play as many lands as possible.
I had about 9 lands including plaza of harmony and gateway plaza (which are also lands)
Gate Colossus cost zero and Gatebreaker Rams were at 11/11 by the end of the game... So I would say I had about 11 mana on the field.
After the game I had only filled my quest by 5/40 mana. I think this is because I used Circuitous route twice.