You can STEAL WYVERN eggs using the invisibility ability at night

You should tame a low level first get tons of blood packs then tame a high level

Blood extraction syringe + snow owl = easy blood packs to tame your first desmodus

Steps to Tame a high level Desmodus with 100% Effektiveness (you need a low level Desmodus to start) :

Step 1: Tame a Stego/Andrewsarchus and saddle them (the saddle on the Andrew is essential!)

Step 2: Tame a Moschops of any level

Step 3: Farm 400-600 Bloodpacks

Step 4: After finding your target Desmodus take out your Stego/Andrewsarchus and your Moschops

Step 5: Put all the Bloodpacks except for the last 100 in the Moschops (the other 100 you keep in your own inventory)

Step 6: put the Moschops on "Following: Lowest" and let it follow your Andrew/Stego

Step 7: Aggro the Desmodus by approaching it and let it grab the moschops, the Desmodus will eat 10 Bloodpacks from the Moschops' inventory and then drop it, this will raise its Effectiveness by 1-3% (repeat this until the Desmodus is at 100% Effectivness. Do not unmount while doing this!)

Step 8: once the Desmodus is at 100% Effectiveness unmount and offer yourself up to the Desmodus. It will grab you and eat 10 Bloodpacks and then drop you.

Step 9: after it dropped you immediately mount your Andrew/Stego again. And let it grab the Moschops again so it's Effectiveness goes back up to 100%

Step 10: Repeat Step 8 & 9 until the Desmodus is tamed.

This will allow you to get perfect tames.

Babies CAN EAT MEAT as a baby to raise them.

They can't dismount you from an Andrewsarchus saddle sit safely within the cockpit and pick off the bats you don't want

Use tames that is carry-able by the desmodus that's on wonder and passive and get the desmodus to pick it up several times and this will increase taming effectiveness .

Make sure to have parachutes because they fly up when taming and will drop you.

Babies take bloodpacks as food when raising.