This is the Discouragement cube from the Portal 2 Portal gun mod, The discouragement beam can be deflected using the discouragement cube. this if from the I chun portal gun mod version 1.2.5- 1.6.4 but only can appear in 1.2.5 and 1.3.2, other than that it is still findable in the mod's jar file but is not in version 1.4.2-1.6.4. I also play Portal 2 so I know that the design is right