Here is the list of weapons that have been confirmed for Halo 4.
http://halo4nation.com/weapons/
What other weapons do you think will appear later?
Rocket pistol is called ‘sticky detonator’ 
Here is the list of weapons that have been confirmed for Halo 4.
http://halo4nation.com/weapons/
What other weapons do you think will appear later?
Rocket pistol is called ‘sticky detonator’