Casting a Couch Spear is a mount and blade technique that continues in Bannerlord, that is, when a player with a spear on a horse unleashes a powerful attack against an opponent. However, it does take a bit of practice. When you land it correctly, you can do great damage against an opponent. You want to learn how to hone in on to help your troops win a battle early on.
First you need to find a spear that has the ability of "couch spear". You can see if she has it by hovering over the weapon and see if you have the highlighted ability. It should show up in the little tabbed window that pops up detailing weapon weight, damage, weapon level, and additional info. If your spear doesn't have the couch spear ability, you won't be able to perform it on horseback. If you see it, you should be good to go.
When you have your spear in hand with the ability to throw the spear, land it, you need to reach a reasonable speed with your horse. It varies depending on the creature you are driving. When you reach sufficient speed, press the attack button and your character will bring the spear back. Once you've launched the attack, the spear shoots out in front of you and your horse, stabbing the enemy you're heading towards. Above your health and your horse's health icon, you should see a spear going up and down, indicating that you are performing the Couch Spear attack. If you land it correctly, you should deal a lot of damage, potentially killing enemies with one hit.
The technique relies on speed and timing, so try to take your time to master it. The Couch Spear attack is formidable, so use it to rout enemies before your allies take too much damage.
