Ok. I am deeply interested in QMs statement that it is possible to slay Morpheos with the thread if we choose correctly. So let's take stock of what we have and what we know of who we are fighting.
1. Scrytegon Morpheos is one of the youngest great war wizards.
2. Scrytegon Morpheos was targeted and deceived by Slannesh.
3. Scrytegon Morpheos bested a keeper of secrets.
4. Keeper of Secrets are masters at high-speed warfare, illusions, and are comparatively weaker when it comes to tanking blows.
5. Scrytegon Morpheos has a lithe body that mirrors the body he had in life, which means he likely possesses a graceful and dance-like fighting style.
6. Scrytegon Morpheos is an egophage par excellence.
7. Here is what QM says regarding egophages.
The main disadvantage egophages have is less that they are not good at combat in close quarters but that egophages have to physically focus their vision on a person or persons. It does not scale well unless you have some truly grody tech, because the only direct network connection everyone has is the Black Noise, and the black noise is full of infohazards that behave like starving sharks after chum when someone moves too loud inside it. Egophages can absolutely be a force in combat and most pneumatics have cyberpsychic training for this reason - otherwise blanks resistant to their psychic powers could just kill them with hacks that the pneumatic would have little way to counter.
You want stealth and range as an egophage so you don't get targeted by too many people at once to manage and die.
8. The Night Witches have been provided with the highest quality gear to minimize the amount of illusions Morpheos can impose, but that still leaves him with cards to play.
9. Scrytegon Morpheos is capable of dueling the bronze king if he fights alongside Hyperion.
10. The hotwire enhances timing, reaction speed, and combat focus, but not agility, mobility, or physical speed.
11. The risk of using the Thread is that the witches, including Harmony, could get tangled up together amidst the trees and illusions.
12. The witches are places into squads that share the same enhanced wire suit, which means that each of the witches in our squad share our enhanced timing, reaction speed, and combat focus, but not agility, mobility, or physical speed.
13. The witches in our flight are dead women walking. Willing martyrs one and all.
14. The night witches together were almost able to slay Theia by acting as one formation, prior to upgrading their suits.
Based on this information I make the following presumptions. Morpheos is incredibly fast, prefers to fight at range, and as an egophage will have great difficulty if targeted by too many people at once. While incredibly fast and stronger as one formation, the witches' strongest skills are not mobility, agility, or physical speed, which happen to be Morpheos's strengths. So what counters these strengths? Of the three options presented, I argue it is attrition. When someone can quickly jump around the entire battlefield and is extremely slippery, while the battlefield is covered in trees that could tangle an unbreakable thread that could leave its users trapped if issued, the option that offers the least likelihood of a catastrophic failure where most of the witches get wiped out is attrition. I originally wanted to do hit and run, but reconsidered given what we know about egophages, how one of the goals was to gather captives, which is not a goal since none should be taken alive, and how the plan was said to TAKE FULL ADVANTAGE OF YOUR MOBILITY, which the hotwire explicitly does not enhance! I just wanted to make this post. I may edit this post later.