Bladeweave is a Special Move that many pet types can get. This thread is going to focus on using Bladeweave on a Cu.
Bladeweave randomly chooses between those 7 specials when it is used by the pet. Bladeweave requires Bushido as a passive when you place it on your pet. So the cost of Bladeweave is 500 points for Bushido and 100 Points for Bladeweave.
When bladeweave uses Bleed, it will remove bleed from the Cu Sidhe. When Bladeweave uses an ability that requires Ninjitsu, it will add Ninjitsu as a passive skill to the pet for free.
A Cu is not from Tokuno so it can not get Bushido or Ninja as a Active skill.
When the taming revamp came out, tamers found that if they chose bladeweave, it would remove Bleed from a Cu. Bleed is the most unwanted ability a Cu naturally has and it uses mana for a low return in damage.
Mana Costs for pets are Here.
Because the Cu now does not have Bleed anymore, this can lead to some interesting uses of Poison abilities that a Cu could not otherwise receive. But, that is not the point here.
An interesting fact brought up by @Quickblade is that you can change the Mode of Bladeweave if you have UO Assist and he has only been able to see this menu on a Mountable pet. "you have to make a maccro with uoassist , that mount your cu sidhe, and as you are mounting it, you left one-click it "
He helped me change Modes for testing. When you select a mode it will stay as selected if you transfer the pet.
In Offensive mode the pet will use AI, Bleed, Mortal, Paralyzing Blow, and Crushing Blow more often.
In Defensive mode it will use Block and Feint more often.
In either mode it will use all of the abilities randomly.
The mode made a difference when testing.
Armor Ignore is a special move that costs 100 points:
It does 90% damage to a target at the value of a normal attack but with the target resist being 0.
So if the targets resist is 10 or less, you would get no damage increase.
Armor ignore has the most single target damage to a high resist target special that we have to choose from.

Bladeweave randomly chooses between those 7 specials when it is used by the pet. Bladeweave requires Bushido as a passive when you place it on your pet. So the cost of Bladeweave is 500 points for Bushido and 100 Points for Bladeweave.
When bladeweave uses Bleed, it will remove bleed from the Cu Sidhe. When Bladeweave uses an ability that requires Ninjitsu, it will add Ninjitsu as a passive skill to the pet for free.
A Cu is not from Tokuno so it can not get Bushido or Ninja as a Active skill.

When the taming revamp came out, tamers found that if they chose bladeweave, it would remove Bleed from a Cu. Bleed is the most unwanted ability a Cu naturally has and it uses mana for a low return in damage.
Mana Costs for pets are Here.

Because the Cu now does not have Bleed anymore, this can lead to some interesting uses of Poison abilities that a Cu could not otherwise receive. But, that is not the point here.
An interesting fact brought up by @Quickblade is that you can change the Mode of Bladeweave if you have UO Assist and he has only been able to see this menu on a Mountable pet. "you have to make a maccro with uoassist , that mount your cu sidhe, and as you are mounting it, you left one-click it "

He helped me change Modes for testing. When you select a mode it will stay as selected if you transfer the pet.
In Offensive mode the pet will use AI, Bleed, Mortal, Paralyzing Blow, and Crushing Blow more often.
In Defensive mode it will use Block and Feint more often.
In either mode it will use all of the abilities randomly.
The mode made a difference when testing.
Armor Ignore is a special move that costs 100 points:

It does 90% damage to a target at the value of a normal attack but with the target resist being 0.
So if the targets resist is 10 or less, you would get no damage increase.
Armor ignore has the most single target damage to a high resist target special that we have to choose from.