All Will Be One deals damage whenever you put counters on permanents or players, enabling a wide range of combos with planeswalkers and proliferate cards. Commander players quickly discovered loops that let it repeatedly ping the table for lethal, which are now documented on combo sites. It also adds incidental damage to decks that already lean on +1/+1 counters, loyalty counters, or oil counters from its home set. That combination of synergy with new mechanics and flashy combo potential has kept interest in it high.