Bring duels back please!
Mercaneries is a mode which is played far less.
Battlegrounds is not for everyone but it since it has more players ( I assume) it gets all the attention.
Also without paying money it is difficult to make some new decks with craft material for new players. ( Not for me since i been playing this game since 2014 and hit the legend couple times)
Duels was everything for me in hearthstone for a year I only played that mode and it was my get away from standart meta which barely changes btw!
Arena updates are ok , though could use some more creativity. ( its been couple months now since they made a new thing in the draft which was to give legendary in the beginning of the draft.)
So please bring back duels or a new mode like that call it dungeon i dunno!