Ok, I've been trying for a few weeks to get Malboro Tentacles, and Dragon..

I will tell the way I did it. I didnt junction magic to prevent status effects because even if you do get through the bad breath attack fine, the battle is still pretty long and hard. What I did to get malboro tentacles was get lucky. If you don't have odin, get him, If you do have odin hope for the best at the begining of the fight and watch Malboro get cut in two. Another way to get malboro tentacles is to have the skill "initiative" junctioned on someone who has mug. Have this person have then right away at the very start of the fight use mug. This way, you can get some malboro tentacles just before it does bad breath.
Now to get a dragon fangs is much simpler. You have to fight dragons, but i'll give you the easiest one to fight. The blue dragon will drop it after he is killed. If it does not drop it after the first time you fight, keep fighting because it also gives you fury fragments which can be turned into aura magic and what not.

Have Squall junctioned to Diablos and Pandemona with the Mug, Darkside, Initiative, and junction Stop or Triple to his speed (to get 100 Stops just use Time Mag-RF and convert 20 Wizard Stones to them; to get 100 Triples draw them from Odine or Abadon when you fight them.) Junction Rinoa to Siren and equip 100 beserk, 100 confuse, and 100 Blinds or Pains to your status defense and junction 100 death to your status attack with treatment ability,and a GF with Spd-J and junction Stop or Triple to your speed (to get beserks just mug 5 steel pipes from Wendigo in the red sand area on the map near Deling City and use ST Mag-RF to turn 5 steel pipes into 100 beserks; to get 100 confusions go to the forests in Timber and draw them from the little mushrooms; to get Blinds go to the forests in Timber and mug Ochu and then use ST Mag-RF and refine 4 Ochu Tentacles; to get Pains mug some Curse Spikes from the red monster found in the Balamb Garden on level B1 where ladder fell. Next use ST Mag-RF to convert 10 Curse Spikes to 100 Pains but be sure to have at least two left over for Selphies last weapon; to get death you need 4 chef's knife from Tonberrys which can be found at the Centra Ruins. Next use L Mag-RF and convert them to 100 deaths.) The third person can be whoever you want as long as they are junctioned to Leviathan with Recover ability.

When the fight starts Mug him but if you fail don't worry. When he uses Bad Breath Rinoa should just be poisoned,silent,and sleep while everyone else has many abnormal statuses on them. Rinoa should wake up in a little while and when she does just use Treatment on her and then Squall and the last person now if anyones health is low make the third person use Recover on them unless it is Squall. Now Squall should get in at least 2 to 3 turns use them to Mug and evryone else should get a turn or two but don't use Rinoa until Squall goes twice and then just attack with her and the Malboro should die, if not just attack or recover with the other person. When Malboro gets another turn he may use Dissolving Acid or Bad Breath, if he uses Bad Breath again then do as before and attack with Rinoa and he should die but if not just attack and use Darkside until you are able to use your Limit Break and he should die.If you managed to mug you will recieve 12+ Malboro Tentacles if not you will still get 6+ for winning the fight.