The summoning chapter of anima mentions that you can perform invocations with the great beasts as well as the arcana, but I can't find info about that anywere. Is it in the upcoming arcana book? I can't wait for that book to be translated.
Invocation
There are some in the Arcana Exxet, but the main purpose of that statement was to note yes, you can make your own invocations (at least the GM can, or players through GM approval).
And yes, there are new summoning options in the Arcana Exxet book. I'm working on the translations, and the two additional summoning chapters will be worked on when I finish the Sheela. If this week hasn't been any indication, the work has been slow. I'm hoping to have the last 3 Sheela done by the end of this weekend though, if not today. I haven't even read the summoning chapters yet, but it looks like they have some good stuff in there.
i have some homebrew aeon summons, nowhere near fit to release to others right now. i agree with lia valenth; that is probably there to allow custom stuff.
It also plays into the fact that Anima was supposed to be the Final Fantasy RPG, but Square said no. So, Anima Studio decided to do his summoning thing, and put in that line so that people would be encouraged to create something like the traditional FF summons, Shiva, Ifrit, etc, without stepping on copywright laws. I think some of the other communities, the French, Spanish, and Official English forum boards, have come up with some interesting summons. I don't have links handy atm, but could perhaps post some in the near future, after looking around a bit, if people are interested.
That would actually make a whole lot of sense. Kinda makes me want to look these up now, and punish my players with them. XD
And links of creatures, not all of them summonable. But most done by the fan community, in one language or another.
First is in French, and will require translation for those wanting to use it. On the other hand, it's actually a link to a French site that has some other useful Anima stuff, and even a very small English section. This link is specifically to the French Bestiary files the guy hosts, but digging around, you can look and see what else is there.
http://projet.animajdr.free.fr/download.php?list.8
Most of the rest of these are links to various threads on the official forums, that are creature related. Pick through, but they have some interesting things in them. Some of these I've read, some I haven't. You'll have to pick through and see what's useful to you. Also, not all are summonable, but this list does give a good list of beasties in general.
Beasts meant for summoning to create heat and cold: http://cipher-studios.com/AnimaBB/index.php?topic=5342.0
A small collection of creatures: http://cipher-studios.com/AnimaBB/index.php?topic=4553.0
Another small list: http://cipher-studios.com/AnimaBB/index.php?topic=4492.0
A Grindylow (monster from English folklore waiting in bodies of water for pray): http://cipher-studios.com/AnimaBB/index.php?topic=4221.0
A couple of Bladeling type creatures: http://cipher-studios.com/AnimaBB/index.php?topic=3907.0
Another collection of creatures: http://cipher-studios.com/AnimaBB/index.php?topic=3166.0
And yet another small collection (Starting to notice a theme yet?
):
http://cipher-studios.com/AnimaBB/index.php?topic=3782.0
This is a translation of one of the French bestiaries. It's not great, but gets most of the idea across. Perhaps something to tackle in the future, would be translating some of the really good stuff from the other communities (French and Spanish, and maybe even some of the German): http://cipher-studios.com/AnimaBB/index.php?topic=3829.0
A single beastie, with a link to quite a few nice ones: http://cipher-studios.com/AnimaBB/index.php?topic=3415.0
A link with lots of creatures, with even more links to some of the Spanish and French threads and compendiums: http://cipher-studios.com/AnimaBB/index.php?topic=1522.0
A Spanish compendium with characters, artifacts, and creatures. Will require translation: http://www.megaupload.com/?d=RX4M3PXT
And the fun stuff, invocations, including a rendition of Shiva and Cthulhu: http://cipher-studios.com/AnimaBB/index.php?topic=1429.0
And the comment thread for the above: http://cipher-studios.com/AnimaBB/index.php?topic=1535.0
MOOGLES!!!: http://cipher-studios.com/AnimaBB/index.php?topic=1349.0
Fan created Great Beast, approved by Anima Studio: http://cipher-studios.com/AnimaBB/index.php?topic=1259.0
And finally, a single creature, the Chaff: http://cipher-studios.com/AnimaBB/index.php?topic=40.0
I hope those give you guys some ideas. I know there are more threads out there, but that was a quick cursory glance. Enjoy.
Thanks for the links, I especially like the whole invoke Cathulu into peoples dreams thing.