First you want to have a good amount of ascendant items

Then you want to attack it with your character block bite attack with a shield, the acid spit is like artho breaks all armor in one shot so id advice to dodge once it performs an acid breath attack shield yourself but allow it to hit you a 3 times in the same breath to stack its debuff X3 right after itll inhale once inside act quick because it does damage but drop 2 ascendant items in its mouth or at least for a 150, levels 80 and lower seemed to work with 1 item, after doing so itll knock out go up to it and ride it, itll performer a roulette where it asks for 3 resources farm those with the vacuum attack and boom you have a tamed Gargantar levels 90 and above tend to take about 36 percent taming after one of this cycles so be ready to be their a minute on 1x.

Use a riot shield for best visibility when blocking its attacks. Bring plenty of medical brews as higher leveled creatures do lots of damage. Aggro it, and run as best you can because you will eventually get stuck in its model while it chases you. Let its acid spit and/globs hit you for at least 3 stacks of debuff and it should inhale you. Quickly drop at least 2 pieces of high level gear. Broken armor and equipment works just as well as functional gear for this case, but it will be lost when eaten by the creature. After it spits you out, quickly approach and "Ride" while and complete its 3-part cycle of minigame. A 135 gargantar takes 3 complete cycles of swallowing and minigames to tame on 1x official settings. These things are extremely tanky, even in the wild, and can inhale creatures up to the size of Karkinos, including wyverns. Be careful and happy hunting.

Go naked with an okay shield, hit it a punch, shield its melee, tank its acid with meds, it’ll suck you up, then drop some useless ascendant stuff like saddles, pikes or whatever. 2 for level 85 or over. Pop more meds and hop on. Collect resources as instructed.(Ragnorak Volcano is super easy for this).

Enjoy your Dyson Jabba the Hutt 9000.

So bring a shield best thing I didn’t even know was gonna work. Acendant gear knocks it out in one shot and broke. Armour works as well. You can bring your own armour but it’s gonna be melted quick don’t bring your best maybe bring multiple sets and as they break feed them to him. Find an area that has stegos and trikes for the cretin as for some reason this was my biggest issue good luck dragon tamers

Taming easy guide:

So you need to let it vomit on you, no the spit ball attack that works similar to the centerpieds spit it breaks armour. Let it vomit on you to build x3 status affect down the bottom right. After that it will swallow you. Drop items higher rarity items means less is needed. That will knock it out and spit you out. After that you complete the mini game by gathering the materials it asks for. You continue till tamed. If you fail you must start back from the beginning.

First you need to aggro this fat guy. He needs to spit his brown bone throw up gunk and you need to get covered. He then will vacuum you up. Then you must drop loot when you are vacuumed. He then will go to sleep and you can ride him. You will go through a mini game where he requests certain things to eat. Keratin/raw meat/raw prime/wood/stone/metal. (I may be missing something). Do this three times. He kicks you off. You do the process again until tamed. I did this with flak armor on. He melts it pretty quick tho with other attacks. If you die after being kicked off you do not lose taming effectiveness and can come back to finish.

Sincerely, a guy who died 12 times doing this day of release.

Taming works by getting spat on then swallowed. While in there you need to drop a high quality item so it gets knocked out. Just jump on and it's gonna roll a material you need to harvest(Stone/Wood/Keratin(not Chitin)/Metal/Prime Meat/Meat). After 3 rounds restart the process until it's tamed. Eats stone and sulfur btw

Punched it, it eventually tucked me up, and there's a prompt that tells you to drop weapons for taming...never tamed it though.

🦖 OFFICIAL GARGANTAR TAMING GUIDE (v924.1)

Unlike other Fantastic Tames, the Gargantar cannot be knocked out or passively fed from your hotbar. It utilizes a hidden "Digestive Submission" mechanic. Because it has the ability to swallow players whole, you must tame it from the inside out.

Step 1: The Naked Offering

The Gargantar refuses to swallow anyone wearing armor or carrying heavy weapons. You must strip completely naked. Place exactly 100 × Narcotics and 20 × Superior Kibble directly into your personal inventory slot (do not consume them).

Step 2: The Ingestion Phase

Find a wild Gargantar. Walk directly up to its mouth and use the "Surrender" emote (Hold t → Emotes → Surrender). This triggers its ambient AI to view you as easy prey. Wait for it to activate its "Swallow Whole" animation.

Step 3: Inside the Belly (The Tickle Trial)

Once swallowed, you will enter the Gargantar's stomach bay. You will begin taking minor torpor and acid damage. Do not panic.

• You must immediately equip a Torch or a Therizinosaurus Feather (if you have one).

• Spam your primary attack button to "tickle" the stomach lining.

• Every 5 seconds, open your inventory and manually consume one Narcotic to match its digestive rhythm.

If done correctly, the Gargantar will vomit you back up after 3 minutes, and its taming bar will instantly jump to 100%. If you die or pass out inside, the taming bar resets, and you will have to find a new one.