Clousers work for both fish and you can get some really big Pike to hit a Walleye size Clouser.
As far as dedicated Pike flies, there is nothing in my opinion that works better than the Reynold's Pike Fly. I have modified it by adding the heart bead. It covers the only tooth vulnerable spot making it a nearly indestructable fly. I don't think color matters much with this fly. Pike blast it.
EP flies work pretty good as well. They don't stand up to the abuse a Reynold's Pike Fly will.
The Dahlberg Mega Diver is a good fly as well. You can tie them with a rabbit tail, as I guess Larry Dahlberg does these days.
For the leader, I start off by tying a Bimini twist in generally 20lb. line. I cut the end of the loop formed by the double line and lightly furl it. I then tie an overhand knot in the end just to keep it furled till I tie it in to the steel leader. To do that I take nylon coated steel and bend about an inch over and tie an Albright knot so that there is about 4 or 5 inches of the furled line.
Bimini Twist | How to tie the Bimini Twist | Fishing Knots
Albright Knot | How to tie the Albright Knot | Fishing Knots
I make that piece 39" long with the length of the steel and double line just shy of a foot after a knot for the fly. I then make the butt end of the leader by making a perfection loop and cut it off at 39"
Perfection (Angler's) Loop | How to tie the Perfection Loop | Fishing Knots
I then put in the mid section of the leader with a blood knot, then cut it off at 39" from the blood knot.
Blood Knot | How to tie a Blood Knot | Fishing Knots
Blood knot those pieces to the first piece you constructed. This makes you a 9' Pike leader.
To put the fly on you have a couple of options. You can crimp sleeve it. Crimp it if you use that. Don't rely on pressure to keep the fly on. You can use a knot called a twist melt. It's just what it sounds like. Put the end of the leader through the eye of the fly or a clip, then twist it for an inch and a half or so. I said use nylon coated, because this is the knot I use, you can take a lighter and melt the nylon. I have never had one come loose and I have used them a lot for years.