ULTRAPORTAL

ULTRAKILL's movement and guns inside Portal 2's test chambers.

You play Portal 2's own single-player campaign, but you move like V1 and you are armed. The portal gun stays in your hands; ULTRAKILL's guns sit next to it on the number keys.

What you do

• Move like V1: slide (hold Ctrl), dash with three stamina pips (Shift), ground slam (Ctrl in the air) and slam bounce (jump as you land), slide jumps, dash jumps and up to three wall jumps.
• Three ULTRAKILL guns: Revolver (1, pierces one target), Shotgun (2, twelve pellets), Nailgun (3, hold to fire). 4 or Q brings the portal gun back. While a gun is out the portal gun can't fire, so you never place a portal by accident.
• Guns that change the chamber: turrets blow up, cubes and loose props get shoved across the room, security cameras drop off the wall, breakable glass shatters and pedestal buttons get pressed from across the room.

What each game brings

• Portal 2 is the game you play in: its campaign, chambers, turrets, cubes and portal gun.
• ULTRAKILL brings V1's movement rules and its real guns: on first Play a small setup tool reads your own ULTRAKILL install and builds the first-person Revolver (with V1's arm), Shotgun and Nailgun models and the gun, dash, slam and jump sounds on your PC. Nothing from either game is in the download.

Good to know

• Single player only: this version has no multiplayer.
• Shots don't travel through portals yet.
• Some glass in the campaign is part of the story; breaking it early can skip a scripted moment. Chambers were built for Chell, and V1 can skip parts of some of them.
• The mashup sets Ctrl, Shift, 1-4 and Q when a map starts. Jump stays Portal 2's own. If you remove the mashup, rebind those keys in Portal 2's keyboard options.
• It installs next to other Portal 2 mashups. One that ships its own portal2_dlc3/pak01_dir.vpk shares a file slot with the gun models: with it installed, the guns still fire but have no model.

Credits

ULTRAKILL by Arsi "Hakita" Patala and New Blood Interactive. Portal 2 by Valve. Fan mod, not affiliated with either. The setup tool includes UnityPy, fsb5, python-vpk, Pillow and Xiph.Org's libogg/libvorbis (all MIT/BSD-style licenses). Built with Claude.