
Portal 2: Community Edition (P2:CE) is a community-maintained version of Portal 2 that significantly enhances the way you make and play content, offering new capabilities such as a brand-new scripting system, an improved Hammer map editor and significantly increased limits over the original game.

Features previously thought to be impossible in Portal 2 due to the architectural limitations of the Source engine are now possible thanks to a wide array of improvements introduced in Strata Source, an officially licensed, heavily-modified version of the Counter-Strike: Global Offensive (CS:GO) engine branch.
These improvements include (but are not limited to) the addition of native DirectX 11 support, physically-based material surface rendering and a new Clustered forward lighting system with support for Volumetric Lighting. Existing engine limitations like maximum map bounds, entity and BSP lump limits have also been raised or removed entirely.
Performance improvements across the game have also been made in part due to the addition of a native 64-bit port of the Source engine, eliminating any and all game-breaking memory restrictions.

What's Old Is New Again:
P2:CE comes with upgraded versions of pre-existing Source engine tools that make it easier for everyone create and publish their own content.
Updated versions of the classic Source SDK tools are included, containing an array of quality-of-life and performance improvements in addition to the elimination of most common crashes, and a whole host of new community-maintained tools are included in P2:CE as well.
Many existing Portal 2 gameplay elements have been updated or overhauled to support new mapper-friendly features, while retaining backwards compatibility with the original game and Portal 1 mods.
Flexible Modding That Starts With You:
A fully-fledged addon system and a new standalone campaign system lets creators publish anything ranging from simple material and model replacements to entire total conversion mods/campaigns either as standalone add-ons or entirely on the Steam Workshop, free of the limitations of the badly-aged Portal 2 DLC system that once severely strained the mod ecosystem.
Improved Scripting Capabilities:
AngelScript is a new C++-like scripting framework that lets users easily extend P2:CE's gameplay mechanics, letting you create your own behaviors, entities and even entire game modes from scratch.
Panorama UI:
P2:CE also comes with Source 2's Panorama UI framework, used in games such as Dota 2 and CS:GO - the Portal 2 user experience has been given a complete makeover featuring a better user flow that runs on top of a more robust foundation. Modders can utilize Panorama to their advantage in their own mods, allowing them to supply their own custom UI.

Play on and share a wide variety of fresh content on the P2:CE Steam Workshop, available to all new and existing owners of Portal 2.
Your Portal, your game. The only limit is your imagination.
It should be noted that Portal 2: Community Edition is still in an open beta phase, and although it is publicly accessible, the game is subject to crashes, bugs, breaks and other issues. This version is not final and not a release.