THE best way to tame anything is to use an argy cage, simply use like 5 dinosaur gateways made of stone and keep one gate door open before you find a dino to tame, once you do, lead it to the cage and then run out through one of the gaps between the gateway frames and obviously close the door and, tadaa, one stuck dino to tame
Make a taming pen with stone gateways, 2/4 on each side, 1 on the front side, and fill the back side with one doorframe with door and the rest walls. Place a large bear trap in the middle. Trap the allo in the pen in the bear trap so that you can safely close the front side gateway (the rest should be closed. If needed, kill the others. Make a foundation with a staircase on the backside. Now easily knock at tame the allo. This probably works for more dinos but only tried with allo.
The best way to tame an allo is to find the level that you would like and kill off the rest of it's group but if u want all three just get to some high ground and then just start shooting them with tranqs
Highly recommend trapping these guys (4 stone dino gates with doors and 1 without a door in a box formation and a large bear trap on the middle inside and once its trapped put the door on the 1 without a door and enjoy knocking out the allo) and if they are in a pack, kill all of them except for the high level or the Alpha. Learned this the hard way and 3 allos attacked me and almost destroyed my already damaged apprentice flak gear from a recent griffin attack. Fun fact The Allosaurus had a bite force of 3.5k N which is weaker than a modern day animal like the Alligator(13k N) or a lion(4.1k N) but the Allosaurus made it up with is serrated teeth made to slash and tear flesh and its incredibly stong upper jaw and if it bites its prey it slams its upper jaw on the body of its prey and tear the flesh from the body and hence the reason why I named mine Slam Jaw.
A simple way to knock it out is to build a 3Ã—3 room with a gate lure them in with a pachyrhinosarus inside then calm them with the pink stuff and just tranq them make sure to keep them passive to have an easy knock out ;)
It will usually be very difficult to separate one from the pack. I suggest trapping all of them (usually 3 in a pack) in a behemoth gate or ramp style trap and kill the ones you dont want before taming the one you do want.