CREATE TABLE table_65656 ("Game" TEXT, "Date" TEXT, "Opponent" TEXT, "Score" TEXT, "Location/Attendance" TEXT, "Record" TEXT)

Who was the opponent when they played at the Skydome?
SELECT "Opponent" FROM table_65656 WHERE "Location/Attendance" = 'skydome'
SELECT "Opponent" FROM "table_65656" WHERE "Location/Attendance" = 'skydome'