Board Thread:Questions and Answers/@comment-33048115-20180129181157/@comment-32271305-20180129190239

Raises ATK for 1 turn: it always activates as soon as the unit super attacks.

Raises ATK for 3 turns: same, but the unit starts with a lower SA multiplier, so it will cause increased damage only starting from the second Super Attack (on the 3rd turn). Basically, "1 turn" is better than "3 turns", because with 1 turn you get guaranteed increased damage every single time, while with 3 turns you have to be more patient and also super attack constantly if you want to keep that boost.

Raises ATK for 6 turns: it's just like the previous one, but it lasts longer, so the unit can boost his ATK three times (technically twice, because again, these units start with a lower SA multiplier).