shifterweapons

Being both an FPS and an RPG, Deus Ex places much emphasis on its weapons, not only in what the weapons can do but also in their bulk, weight, and if and how they can be upgraded.  Because they are such a large part of Deus Ex, modifications and additions to the game's weapons are a big part of Shifter as well.

1) Alt-Fire.   2000 (the game's year of release) was a long time ago, but it wasn't so long ago that Alt-Fire was new.  While Deus Ex halfway accomplished the functionality with the "Change Ammo" key, it was mostly for show.  (With the notable exception of the Assault Rifle)  Shifter adds a real and proper Alt-Fire to Deus Ex, with a new keybind and Alt-Fires for many weapons.  To give a few examples, the Shotgun will load up an additional shell for a one-two (and even -three-four-five) punch, the Plasma Rifle now has an extra-deadly "bounce" projectile mode, and almost every hand-to-hand weapon can be thrown to do damage at medium distance.  For those weapons which do not have an Alt-Fire pressing the key will simply toggle the scope, if available.

2) Unique Weapons.  Another one of the things Invisible War got right was the addition of so-called "Unique" weapons.  Shifter brings this concept to Deus Ex, adding several to the game.  Examples include JoJo Fine's custom Stealth Pistol, Smuggler's fully automatic Shotgun, and even a fully functional, shoots-through -walls Railgun, complete with a through-walls thermal scope.

3) New and improved ammo.  Some types of ammo were always somewhat trivial or useless, ammos like Flare Darts or Pepper Cartridges, both of which have been improved to be both effective and fun to use.  Shifter also adds a number (limited but growing) of new ammos to the game, ammo types which make existing weapons all the more powerful or versatile.  Explosive bullets, anyone?