Let Mega Altaria ex absorb pressure first, then transition into controlled attacks once your board is stable
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You can only use each effect of "Thundurus the Boltstrike Djinn" once per turn
It gains haste until end of turn." When this creature dies, create a 0/1 red Elemental creature token with "At the beginning of your upkeep, sacrifice this token and return target card named Rekindling Phoenix from your graveyard to the battlefield
Because of this type of structure, he can be apt to getting some bad hands, and as long as you can place down a few good beatsticks of your own (or deal with his support cards) you should be fine