All combo weapon blueprints, in the order they appear on the blueprints menu. Don't forget that if you happen to overlook one you can check through the combo weapons lists in your locker to see what isn't there, and then make that!

Massive Bomb
Fire Arrows
Enormous Bomb
Sticky Bomb
Sentry Cat
Zombie Raker
Ultimate Mecha Dragon
Buffet Cart
ZAR
Tactical Handgun
Tactical RC Gunner
Pummel Blast
Bigger Bomb
Tactical UAV
Elemental Staff
Chuck Axe
Boom Cannon
Hail Mary
Provoked Bear
Electric Rake
Heavy Metal
Flaming Sword
Napalm Bomb
Freedom Bear
Remote Detonator
Pukes o Hazard
Big Bomb
Electric Shout
Huge Bomb
Flaming Helmet
Grim Reaper
Split Shot
Death Mask Reaper
Super Crossbow
Flame Mecha Dragon
Bomb Toy
Roaring Thunder
Sabre Shot
Chop n Talk
Spiked Bucket
Rocket Punch
Super Shout
Ultimate Buffet Cart
Meat Buffet Cart
Boomer Axe
Mauler
Chopper
Tactical RC
Boom Bear
Party Gloves
Fighting Gloves
Drink Buffet Cart
Weapon Cart
Dynameat
Beer Hat
Shocking Touch
IED
Ultimate Grim Reaper
Electroice Staff
Volatile Bear
Iron Edge
Electrofire Staff
Flamethrower
Defiler
Mini Chainsaw
Flaming Gloves
Mecha Dragon
Explosive Chair
Glove Gun
Laser Sword
Pole Weapon
Metal Mary
Dragon Punch
Junk Ball
Helmet Bomb
Decoy Bear
Jack in the Box
Car Bomb
Electric Crusher
Tenderizers
Mecha Dragon Blade
The Slapper
Spiked Bat
Fire Reaper
Super Massager
Pushy Bear
Ultimate Shout
Grisly Bear
Power Shout
Electric Staff
Cuddly Bear
Sledge Saw
Acid Toy
Tactical RC Bomber
Acid Rain
Electric Chair
Blambow
Chest Beam
Knife Gloves
Acid Jar
Jazz Hands