Let him figgure out your middle name on his own! And tell him to stop being an officious prick

Let him know that if he removes you from the will, his grave will be in the backyard and his casket will be a cardboard box.

This doesn't add up, so he has your middle name on the will, so he needs to know what it is to get it off. First he would need to know it to put it on, or if a lawyer wrote it he would know what it was in the context of your name. So either this is a flat out stupid lie, or your dad is just dumb and doesn't know that the name in between the other two names is the middle name

Go out, be successful, change the world and put him to shame.

I would tell him to guess until he gets it right or suffer. Sorry anyone that much of an ass doesn't deserve to keep their money. You may not owe your kids much but as a PARENT of you don't care how well off your kids are than you shouldn't have had any, anyways. Since it's too late for that why would you tell him? He doesn't care to remember it must not be his concern

'If I'm no longer in the will, there's no point in waiting for natural causes.'

I hate how everybody is quick to assume that you are the victim. There's probably a reason he doesn't want you in his will. You're probably a gold digging bitch. YDI.

Say it's something different so he can't take you off.

OP, does he use money as a weapon a lot? There are certain types of abusers who do the "If you don't do what I say I will disinherit you!" as a ploy to control the people around them. They may not even have money, but just pretend they do. Best to give him your middle name and block him from ever contacting you again in any way . Make sure your finances aren't intertwined and go live your life without giving him space in your head.

If I were you I'd call that no father of mine just another person.