Laning phase Buy in order, core opening gives bossted sustained close range fire, burst and reach for core abilities and nesessary speed to stay effective
Early mid game Buy in order though defenses can be delayad and focused by enemy dps. Gives lifesteal for primary attack type, the defenses to commit, counter defense, and more speed
Late mid game Point blank offers a high value, and early armor will leave you a menace forever, after this you can rush leach, maxing tank, or you can get imp burst to really amp your ability dps first. Mag/reach can be delayed