I had misread Frontier Siege as "adds 2 green mana to your mana pool each turn". Yesterday, I found it adds 2 Green every main phases, that's 4 mana in two main phases a turn, that's crazily good. And its "Dragon" option is good for turning flying creatures into removals. I started to build around it. The first thing I considered is putting it into a ramp deck. We can have Genesis Hydra , Polukranos, World Eater , Ugin, the Spirit Dragon in the deck. To get the best outcome, we may add more ramp cards like Voyaging Satyr , Sylvan Caryatid , Elvish Mystic , Nykthos, Shrine to Nyx . In the end, we will get a deck close to the Green Devotion in Grand Prix Seville 2015 top 8. On top of that, I think giving 2 Green mana every main phase is good for Morph , Manifest and some activated abilities because these activation don't require you to pay all the mana cost at once. Maybe, it can synergize with Temur War Shaman and Whisperwood Elemental .
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