Ark has some pretty tough boss fights, but the desert titan must be the easiest of the boss fights I have ever encountered.
How you defeat the boss depends on the level of cheesing you’re willing to accept, if you don’t mind fighting dirty, there’s a method which I have tried and tested, which works without taking any damage.

1. Cheese it From the Ground
You might have already figured that the Ark desert titan boss has a limited range in which it is able to hit you with either its lightning attack or the swarm that protects it.
For this method, you will need a wyvern, it doesn’t matter what type, and a shotgun, or any other gun with the highest damage possible.

All you need do is look up and shoot, and as long as the desert titan remains high enough to be out of agro range, you can continue attacking him without taking any damage.
You might think that this would take longer than using the wyverns, but it doesn’t, if you have 3 people each with 300% ascendant pump-action shotguns, or the highest damage you have, you will do more damage than your wyverns can and will take absolutely no damage.
The reason for needing a wyvern is so you get the engrams, we learned this the hard way, once you’ve taken down the desert titan, if you’re not in agro range, you will not get the Tek engrams to unlock, so it’s very important that you fly up and finish it off with your wyvern.
This is by far the easiest method, but if you are looking for a less cheesy battle, move on to option 2.
2. A Little Less Cheese With Your Titan
To be completely honest this particular method isn’t much harder than the cheesy method but can take a bit of practice to get right.
This method will also take longer depending on how many people are in the fight, but it can be done solo without too much difficulty.
Again, you will want a lightning wyvern, but this time, you won’t be landing on the ground, instead you will be landing on the desert titan itself.

You will need to keep an eye out for the swarm targeting you, in which you will need to make a quick getaway, but once you’re free from their grasp, come back and continue munching on a titan.
Be sure to have either some parachutes or a glider on you during this fight, as you run the risk of being knocked off your wyvern, also make sure the wyvern is on passive and on follow, so if you do get knocked down, it will follow you to the ground, allowing you to get back up there.
3. The Battle Bird
For this one, you will want a Quetzal with a platform saddle, you will also need two players at least to do this one successfully.
Make a 4×4 box with windows on the platform and have one player sit inside that with a very good damage shotgun.
Simply fly the Quetz up to the desert titan and the player in the battle box can unleash a flurry of lead into the desert titan, of course, if you have more people in the box, the boss will go down much quicker.
The box will also protect the player with a shotgun from being knocked off the Quetz, allowing them to focus solely on taking down Ark’s desert titan.
Summary:
All three methods have been tested, both by solo players and larger groups, and have been very successful in defeating the desert titan.
While it will take longer, options 1 & 2 can let you beat the desert titan in Ark without too much hassle, even as a solo player, option 3 is a great option for larger groups taking on the Ark boss.
