This is a guide to a lvl 20 SMN who is fighting the avatars and may need help.
There is a method that will pretty much work overall for all of the battles, with a little tweaking needing to be done for each individual avatar.
What you need:
Yagudo Drink x2
Ether (if none use hi-ether) x2
Steamed Crab x1
Elemental Resistant gear
and if you want, bring a few potions
spell interruption resistant gear
Ok, so heres what you do. You go in, buff up, eat the crab, head up the stairs. Once you get about 3/4 the way up, summon carby, drink a yagudo drink, and use astral flow. Now sick carby on the avatar, get in range, and then have him use searing light. As soon as you hit it, run run run to the bottom of the area, run until you are on the line of where carby's health bar dissapears. Now drink an ether, rest up and wait for carby to kick the bucket. As soon as his name is gone, summon a new one and sick him on the avatar. Now hit searing light and run to the top of the area. Do the same thing, use an ether, and a potion if nessesary, resummon carby and sick him on the avatar. Your yagudo drink should run out about here, so use the other one. Ok, last time, now wait for blood pact to be ready and use searing light one last time, but look out for the 2hour the avatar does, it will wipe out carby, and heavily dmg you.
Now I know that sounds easy, but you have to have all the right things happpen at the right time to with these fights. Heres a list of the things that if they happen, then you should just quit and let it kill you so you can start over.
Carby dies before he gets searing light out.
Astral Flow wears off.
Avatar uses 2hour and kills carby
carby gets interrupted
you forget the ethers
your searing light misses (yes, it can miss, but it doesnt totally miss, it only does 50% of the dmg)
Now that you know the technique, ill give you the avatar, the location of the quest giver, and the little details for that avatar fight.
Ifrit: person next to Ronta-Onta in Kazham, (J-9), ifrit does massive dmg, so bring a potion or 2 along
Ramuh: person next to Ripapa in Mhaura, (I-9), Ramuh does paralyze, which can make carby's searing light fail, use paralyna or a potion (Remedy?)
Leviathan: person next to Edhal-Tedhal in Norg, (H-9), leviathan uses gravity, so make more running room, and make sure carby gets all the way to him before u hit searing light.
Titan: person next to Juroro in Port Bastok, (I-8 ), Titan has really high def, and he uses his 2 hour right as carby prepares to do his 2nd, so wait a little bit or speed up a little bit on ur 2nd.
Shiva: person next to Gulmama in Northern Sandoria, (E-7), shiva has high evasion, so searing light may miss sometimes.
Garuda: person next to Agado-Pugado in Rabao, (G-9), garuda likes to use her 2 hour too, and has blink, so make sure carby hits her 3 times before u set off searing light.
Ok, so now for some quick facts to answer anymore questions you have
You can do the avatar fights once every 24 hours
You can fight a different one once every 2 hours
You cannot fight them again with the 20 cap after you kill them once with it
You can get the avatars through the 60+ fights too
It may help if you cast buffs on carby
This is the fight with the real item of the fork, not the key item
You must be alone
Buffs will NOT wear off if cast on you before you are warped there
It helps if your summoning skill is capped, it helps ALOT!
quickly giving credit where credit is due, i did indeed get the names and coordinates from allakhazam, but thats the only thing
Now i hope this guide helps all you summoners out there, if u have questions my E-mail is
Darkwolf27@gmail.com