"Mass Spell and Trap Remov(al/ers)" refe(rs/r) to cards that can take out a lot of Spell and Trap Cards on the field at the same time. Some examples include "A Wingbeat of Giant Dragon", "Giant Trunade", "Gigantes", "Harpie's Feather Duster", "Heavy Storm", "Malevolent Catastrophe" and "Sacred Phoenix of Nephthys".