Twice as long. As fast as the original would be "0x slower" or "1x as fast".
People should just use duration instead of speed as you did at the end: "takes twice as long", "takes 1/3 of the time..."
People should just use duration instead of speed as you did at the end: "takes twice as long", "takes 1/3 of the time..."
I have played a fair number of incremental games and this quickly became a pet peeve of mine. So many will say things like "2x more" and it will actually be "2x as much". Fortunately, I don't recall any which actually switch between the meanings but it's so commonly a guessing game until I figure it out.