Alright, well, let’s start with the fact that you put a lot of emphasis on how you would get slaughtered “if” you couldn’t find all the Artifacts and would get steamrolled as a result. Both of those are honestly quite the accomplishment; for the former, the first two Artifact pieces frequently spawn fairly close to your starting position (I’ve often seen the first one spawn inside the main) and the game will put helpful location circles on your minimap if you take too long to find one, and for the latter, even with only one Artifact piece, Zeratul’s units and hero are quite formidable, if you’re getting steamrolled or slaughtered, you’re probably doing something wrong. Add onto that the fact that the Cannon and Legion nerfs were apparently so offensive, such “nonsense”, that instead of learning to adjust you quit the game. So I didn’t say you were “bad”, you made those implications yourself.
And before you start thinking that I’m some kind of master-tier elitist, HAH, I’m far from the most hardcore player around here; I’d like to think I’m pretty good, I’ve done most of the campaigns on Brutal and all that, but my micro’s not the best, I make F2A armies, I’m not out there soloing Brutations with a level 1 Raynor or anything, I’m just somebody who’s pretty decent at RTSes and enjoys playing Co-op for fun. If I was reading those implications and think the nerfs were justified, that should mean something.
But speaking of which, let’s start with the pre-nerf Cannons: completely broken. For other commanders, the trade-off of building entirely static defenses was that their mobile offense suffered as a result, but not so for Zeratul. You could easily just cover your bases in Cannons and then clear the map completely risk-free with Shades and your hero. Who needs an army when you can just teleport a few dozen Cannons wherever you need them and suffer no costs if you overextend and lose them, since their physical forms are safely back in your base. The perfect defense, the perfect offense, all for 0 gas cost and 0 supply cost. If that’s not broken, I don’t know what is. Thing is, even after the nerf (even at 400 minerals), they’re still quite usable, quite strong, you just can’t rely on them entirely, you have to be more strategic about where you place them for defense and think more carefully about when you use their Shades.
As for the Legions, that nerf was pretty simple: their low cost made them undervalued by players. With full mastery, they cost the same as a Stalker, so I’d see people using them to clear expansion rocks and clearing maps without ever having to make actual units. They’re still quite good now, you just need to use them in the same way as other commanders use their calldowns; save it for an emergency or to amplify a push.
And I know what you’re thinking, “but this is PvE, we don’t need balance, we want to feel powerful!” To that, I’ll just link you this thread from a month ago which covered that very topic. Nerfs to come with compensation similar to Hearthstone's full dust disenchantment - #15 by GhostWhoWalk-1854
), but I could see why the nerfs were needed.