The deck packs flame slashes for that very reason. Flame slash deals with most heavy body turn two drops (wall of omens, spellskite, etc) and spellskite isn't useful as an answer to something already targeting it. On top of that, even if you get a turn two spellskite, you could still be in for a loss. Two copperline gorges fuel the deck with the mana it needs to win regardless. Turn one for the elf, turn two for a slash to deal with the spellskite and a strobe/mutagenic growth combo for the win regardless. On top of that, his board packs a set of nature's claims. Both are easy replies to the spellskite that let a turn two win happen.
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His deck is built for standard, yours is not. It's not a worthy comparison. On top of that, the earliest you have an answer for anything he does is turn two, and if he's on the play, you have no response at all. So it's actually reasonably plausible for his deck to turn two infect win, even against the deck you listed.
Try Two mana (one green and one red, or better, copperline gorges) an assault strobe, the elf, and mutagenic growths/groundswell. Between 5 and 6 cards. Tougher, but not unreasonable.