15w47a it was working (i beleive) then in 15w47b, all my trigger related command blocks stopped working. Reason: They all said "/execute @e[score_effect=50] 99959 68 99997 setblock ~ ~ ~ redstone_block" or something similar. They all had @e. When I changed the @e to an @a, it started working.

"/say @e[type=Player]" also doesnt work.