User blog comment:FairyRaven/Fairy Tail Chapter 448: Fight the Power! Review and Commentary/@comment-24264679-20150817160616/@comment-96.24.244.24-20150817175018

Simply brining in other guilds to take out foot soldiers would be a waste of space and time consuming. That is way to many characters to draw on the protagonist and Antagonist side. Hiro mashima isn't going to draw over 100 characters when he could just focus on 13 important characters on the protagonist side and 13 important characters on the antagonsit side. That is 26 characters to draw vs near a 100. The foot soldiers aren't a threat as we seen how Fairy tail easily dispensed them. Also before that we had 4-5 members taking on 2000-100000 foot soldiers with no problem during the Orichi fin and Avatar arc. So you could leave foot soldiers like that to the lesser members of Fairy tail such as Romeo, Macora, bisca, Alzack and etc. For people like Marin you could have people like Elfman, Pantherlily, Rijinshuu and Lissana fought those characters.

Bringing in other guilds will just turn into a giant mess. They want be any real factors in the big fights and brining them in the little fights would just be a waste of time and space. The more characters Hiro mashima have the shorter the fights will be and thus the crappier. At the same time Tag team battles only really work when characters of the same level fight side by side. No Guild really has what it takes to be up there with Fairy Tail. During the GMG Fairy Tail only put 5 powerful members vs the 15+ powerful members they have in thier guild into battle and they still won against other guilds who put all their good members in. Of the good members 1-3 were actually powerful.

Also Sting and Rogue were weaker then Base Natsu during the Tartarous arc given the Tartarous arc happened no later then a month AFTER THE gmg. In which Natsu thrashed them in base during the GMG.