Yeah, that's pretty much it. I had to watch the Golem explode some 20+ times before I got my first Golem Fist, which has an equal droprate as everything else.
Plantera was also rather stingy with the Venus Magnum. Again, it all comes down to randomness.
It's all obfuscated and some of the classes don't decompile with what I used (It worked better in the first few versions of Terraria, but it's obfuscated better now, apparently, to the point that the decompiler fails on a bunch of the important classes now), but you could use bomb statues to make a ton of bombs, then bomb your way to hell on some small maps and kill the WoF on each, then look at the maps in TEdit to see if any of the stripes ever go off the map or hit the ocean - or ask on the official forums if anyone had them hit the oceans, etc.
Or, if you're using TEdit anyways, just give yourself a bunch of 100-stacks of bombs instead of going through the tedium of bomb statues... Also, I've always seen the stripe convergence point as being pretty much dead center, which makes sense as far as how the game handles map sections. But then again, I really haven't checked that many different maps.
And yes, smashing altars does absolutely cause pockets of Hallow AND Corruption/Crimson every time you break one. Merely cordoning off the initial burst is effectively meaningless if so much as a single altar is broken.
Author
Topic: Terraria - 1.3 released. Big Patch! (Read 1261551 times)