Pretty much play your curve and be very aware of everything that your opponent can do any given turn. You usually will not be speedy enough to take out aggrowth or tempo order early so anti agressive threats like stormrunner and forcing them away from you with stuff like oculus is also a good idea. Against decay a well timed machinated or desperation might be enough to send the decay player to there knees overall though the matchup is in favor of them a bit. MES desperation and machinated are your friends, when to transition into going for idols is a pretty hard decision, but in pretty much every MES vs. MER there is a tipping point where It is unlikely that you will able to keep destroying your enemies structures if you play it right this is in your favor.
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nice deck