On level 1 increase the distance of shadow charge to ambush heroes against your own tower (great combo with firestomp whith overpower hook). Next one is firestomp gives u aura, that makes any foe uncomfortable to hang around u. The third that increases the stun of shadow is great to ensure kill. Level 10 is critical to go for apocalypse, works great with any ranged assasin to party with. Next upgrade comes for the waves return, aditional damage to one shot the minions (very important when u fight 1v1 surrounded by tons of them). The next for the movement and damage after firestomp, is critical to finish heroes down.and level 20 blink is great for your survival.. gg