User blog comment:Lord Zeref Dragneel/Top 25 most powerful characters/@comment-25111584-20150812160455/@comment-1153699-20150813031833

I don't see Kagura or Minerva one-shotting Bluenote (casually) or Ikusa-Tsunagi (breaking him apart as if he's made of rocks). Whether they even win or not against either of them is debatable (especially against Ikusa).

Imo, GMG Natsu and Gray (individually) would already give plenty of trouble to GMG Kagura and Minerva anyway.

If I were to make a Ranking / Tier list based on what we've seen so far from everyone, Minerva and Kagura would be waaay below Current Natsu or Gray (possibly way below Gajeel and Erza as well).

Now I'm not saying they didn't improve at all. Obviously they did. But I don't see them having the same improvement FT had.