If you control a “Command Knight” equipped with “Ring of Magnetism”, and another monster, your opponent can and must select “Command Knight” as an attack target if he chooses to attack.
If you control 2 face-up “Command Knights”, and no other monsters, and 1 of them is equipped with “Ring of Magnetism”, your opponent cannot attack because the 2 “Command Knights” are preventing an attack from being declared. “Ring of Magnetism”’s effect forcefully leads the attack to the equipped monster only when the opponent declares an attack, which is impossible for your opponent to do.
If “Umi” is active and you have “The Legendary Fisherman” on the field, your opponent can attack directly. But if you have “Legendary Fisherman” and “Command Knight”, and no other monsters, your opponent cannot attack directly because of “Command Knight”, and cannot attack “Command Knight” because of his effect, and cannot attack “The Legendary Fisherman”, so he cannot declare an attack (but can enter the Battle Phase to activate card effects).
If you control “Patrician of Darkness” and “Command Knight”, and your opponent attacks, you cannot choose the “Command Knight” as the attack target.
If you control “Command Knight” equipped with “Raregold Armor”, your opponent can attack “Command Knight”.
If you control a “Command Knight” and another monster, and your opponent attacks the other monster, you can use “Shift” to select “Command Knight” as the new attack target.
You can choose your own “Command Knight” as the attack target when your opponent attacks your “Dreamsprite”.
“Command Knight”’s effect increases its own ATK by 400 points, in addition to your other Warrior-Type monsters.
If you control multiple “Command Knights”, their effects are cumulative so each will increase all of your Warrior-Type monsters’ ATK by 400 points.
If “Command Knight” is Normal Summoned, Flip summoned, or Special Summoned, its ATK is at least 1600 so your opponent can activate “Bottomless Trap Hole”.
If “King Tiger Wanghu” is on the field face-up, and “Command Knight” is Summoned, the effect of “Command Knight” is applied immediately because it is a Continuous Effect, so first change “Command Knight”’s ATK to 1600. After that, “King Tiger Wanghu”’s effect cannot activate because “Command Knight”’s ATK is not 1400 or lower.
If “Physical Double” creates a Mirage Token of a Warrior-Type monster while “Command Knight” is on the field, take the current ATK (including “Command Knight” Bonus), then apply all bonuses again if appropriate. So a Mirage Token of a 1600 ATK Warrior-Type monster would be ATK 2000 (it copies the 1600 ATK and then gains “Command Knight”’s +400 ATK bonus).