Co-Optimus - News - How to Play Portal 2 Split Screen on Your PC
Portal 2 PC finally gets split-screen co-op | Eurogamer.net
Portal Knights on Twitter: "Vertical split screen is being added to #PortalKnights as part of Update v 1.1! We know this is a popular request, so it's happening... 😉 https://t.co/35poagsJqY" / Twitter