Oh, you have this specific, Unnamed power that works like this!
Oh, wait! The author wated to use the word "Summoner" because it's popular, so now you have a totally different power, that doesn't make any fucking sense!
Also you can destroy a kingdom, but make sure to not ever actually try to fight when it matters! Oh, and now you have less power than when the series started less than 20 chapters ago!
This makes sense!
I don't know what in the fuck this author smokes, but it's definitely crack.