Nickel based alloys are provided comprising from about 7.0 weight percent (wt %) to about 12.0 wt % chromium, from about 0.1 wt % to about 5 wt % molybdenum, from about 0.2 wt % to about 4.5 wt % titanium, from about 4 wt % to about 6 wt % aluminum, from about 3 wt % to about 4.9 wt % cobalt, from about 6.0 wt % to about 9.0 wt % tungsten, from about 4.0 wt % to about 6.5 wt % tantalum, from about 0.05 wt % to about 0.6 wt % hafnium, up to about 1.0 wt % niobium, up to about 0.02 wt % boron, and up to about 0.1 wt % carbon, with the remainder being nickel and incidental impurities. The alloys may be cast, directionally solidified and heat treated to provide articles having a gamma prime fraction of greater than about 50%.