"What's been the impact?"
According to what HSReplay is tracking, this is the set distribution of the 108 cards most commonly included in Standard decks (5% or greater representation):
Journey to Un'Goro: 11 cards (10%)
Knights of the Frozen Throne: 15 cards (14%)
Kobolds and Catacombs: 24 cards (22%)
Witchwood: 7 cards (6%)
Boomdsay: 3 cards (3%)
Rastakhan's Rumble: 6 cards (6%)
Classic: 42 cards (39%)
狗頭人佔左22% 仲多撚過最新個三個expansion加埋