One of the easiest ways to passive tame a Diplodocus would be to try to run under it (The best place is behind the front legs) and duck. If in the right spot and done correctly, the Diplo's hitbox will not be able to reach you, keeping it in the same spot.
Know that it is easiest to passive tame them, which means walking up to them and feeding them
Get a TON of berries, everytime you feed it, it will go up like 3-5%
Have a high speed, high attack flying dino, (high attack in case you "miss click")
HAVE PATIENCE, diplo's are a stubborn tame, they will push you playfully (hence the flying dino)
MAKE SURE there are no carnivores around, if there are carnies around it will attack it there is a chance of it dying, it will get rid of all your hard work, and most importantly, IT MAY DIE (R.I.P. attempted tame #1 + 2 😢)
Plz note I am not an "high level player" that has a giga, I am lvl 50, (51 at the time I wrote this, almost 52) so I am not that experienced, tho I am sorta, I don't know that much about the game
Very easy tame! Just go by a rock while getting hit, so you don’t go far away, and go under the diplo. Keep feeding it mejoberries, and wala you have a diplo. Keep in mind the little bonks don’t hurt so don’t be afraid by that.
Okay I’m new to mobile ark cuz I play the console version but I tried to tame this beast and it was actually not that bad cuz it only took 15 minutes then I just tamed another and another to make my army bigger :)
To tame feed it one berry,walk off and let its food bar go down a few thousand.Come back to it and for me I found a spot right in between its front legs where if I stand it stops moving and sits there basically letting you fill it with mejoberrys till its tamed.If you cant find the little area to stand literally just walk in circles underneath it.
Passive tamed a level 12 (+5 levels) with 15 mejoberries. If you can situate yourself under it’s legs, specifically between the two front ones, the diplo will continue to try and bump you back but will be unsuccessful. It will do this move over and over again, and drain its stamina and hunger faster, which leads to a faster tame.