Dclone spawns on an IP every time a certain number of sojs have been sold. I believe he spawns for every 100-150 sojs sold. Basically, if people sell sojs to the merchant, after about 100-150 have been sold, he'll walk, and then it'll take another 100-150 to cause him to walk again. Whenever you see xxxx stones of jordan sold to merchant, someone sold one. Unless you know at which count he walked last time, the number of sojs sold doesn't tell you all that much, all it tells you is that someone is selling (if you're getting spammed by it, there's a good chance someone is popping him and he'll walk).
Thing is, he only walks on that IP. Bliz has a ton of servers, each have a different IP (only the last part is different), so there's like 150 servers.
If you're lucky enough to be in a hell game (he only spawns in hell) and see the Diablo walks the earth message, the next super unique you see will be Diablo. A super unique is any unique mob that is always there, such as pindleskin, shend, blood raven, etc. Rakanishu (the guy guarding the stones in stony field) is a very popular spot to go to if you see Diablo walks the earth, because he's easy to find, and whatever else is near him should be easy to kill. Be careful when you see Diablo walks the earth, you really don't want a super unique in a dangerous area to be replaced by Diablo clone.
Dclone himself is very hard to kill too, you almost need a character built to kill him. Unless you got a ton of patience, forget casters, he has 95% resistances to everything (maybe a fully synergized bliz sorc with high CM might work, but for the most part he sucks to fight as caster). You'll want a melee class (although he also has 50% PDR), a ton of CB (preferably 100%), max resists with light/fire absorb and max block to make the fight easy. You'll also want a prevent monster heal item on switch because his regen is INSANE (My sorc with slevel 32 FO and slevel 20 CM could not do more damage than he regenerated). He uses the same attacks as Diablo, which is why you want the resists and block, so his lightning or the fire snake attack don't kill you in one go, but unlike Diablo, he also constantly has armageddon on.
Not sure how dclone hunting is as necro, but I doubt it'll work. A psn or bone necro would most likely lack the damage needed, and a summoner will lost his summons to armageddon + his specials way too fast. Personally I prefer a frost zealot for dclone hunting, they're easy to level and zeal + cb rocks.
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