Ir Anuk & Ir Halak Grimoire Cards can be obtained during the fight of Kings's Fall Raid. Ir Anuk and Ir Halak are daughters of Oryx and you need to fight them in 'Last Rites' Mission to get the cards, but we have different tricks where you have both the cards without any loss of health and also without fighting them. Check the Guide below on how to get grimoire cards for Ir Anuk and Ir Halak.
To Begin with, you need to accept the 'Last Rites' mission quest which is on the Moon. Now just make sure you have Icebreaker and a Stealth device because you need a lot of ammos and sneak through the enemies until you reach the Crota’s grave(Follow the Radar Marker).
When you have made it till the Crota’s Grave you need to jump from the hole and just wait there in the water. Simply move in the water, look through the door and you’ll notice a smoking cube in the distance with two large figures beside it. Now here is the Trick you need to take a clear shot right from the water where you are standing.
Note: You'll be spotted by them if you move closer. So Avoid and stay in the water.
Once you have figured them out, shoot at once and let the stealth device replenish again to make yourself ready to shoot. That is once you shoot your stealth device turn red then white, again dark and after fully invisible again, take another shot. If you shoot before the device is full again(visible) then you’ll be discovered and teleported to a room full of enemies.
Hint: Aiming for the head will speed things up the kill.
Once you have taken down both the daughters from Left will be Exalted Hive: Ir Anuk, Deathsinger grimoire card and to the right is Exalted Hive: Ir Halak, Deathsinger card. This is how you do it without any damage. If any doubt does shoot them below in the comment section. Enjoy.