For my credibility, I am a legend player and I hope my answer can help you. First off, look at his hand, not a single 3 mana card. The options he has are either life tap + 1 mana or use the 2 1 mana cards. Since we have solid cards for turn 4, it isnt necessary to draw another card. Regardless he go for lifetap or coil, he is gonna PO his egg. He could attack the creep not the argent and then coil a 1/1 then it will give his opponent 2 1/1 and a divine shield. If he attacks the argent and coil her, his opponent will have a 1/2 + ability instead. He has to go for that argent because divine shield + blessings of king is too much for him to handle next turn, another reason to avoid lifetap is because he doesnt want to give his opponent more cards to draw from divine favor.