I posted earlier with a question regarding beating the Computer on Hard, as Hades, with a Norse Civ.
I had tried around 6 times with Loki, but to no avail.
But a little aggresive strat suggested by someone, and using Odin's RCavs + Valkyres i just ravaged a Hard Hades Comp. The Frost GP is awesome to use when rushing. Heres what i did - rush the TC with all the RCavs and Valkyres you can manage. Stay on the TC, till he brings about all his armies, beating upon you while you try and take down the TC - while the opponent takes you for a fool, getting your army killed trying to take down his TC - BAM - fire the Frost GP. Now while his army cools their heels, go and slaughter his economy .. totally. This shouldve bought you enough time to get a Hill fort up and around 4 Rams out - and that is game over in early Heroic (the comp was still in Classical in this case). As for upgrades - priority is to upgrade the RCav - then Pierce Armor at the armory. And in Myth Upgrades - Thundering Hooves then Aurora Borelias. Infact an error picked up in Aurora Borelias' description. In game, when you open the info sheet of a Valkyre and hover over the upgrade icon - it says Aurora Borelias - Improves the Valkyre's Hit Points and Healing Rate, while actually its improving the Hack Damage and Healing Rate.