Corruption and crimson being able to destroy your jungle is one of the worst game design choices I've seen.

The jungle in my world was generated right next to the original corruption biome and another corruption biome, right on the other side of that jungle, was generated as soon as hardmode started. This is freaking ridiculous. And hardly fun.

About 1/5 or so of my jungle has already been converted, not to mention corruption reaches deep because of the original biome's deep tunnels. I've had helleavators, but they apparently weren't wide enough, because corruption found its way to the other side.

So is there any mod that make it right?

Yeah some prep time is needed before triggering hard mode if you don't want to control the spread of corruption/crimson. In my last game I dug out tunnels to isolate certain biomes, and I if memory serves they have to be at least something like 5 tiles wide. Still, late game there's a powerful tool to get rid of corruption/crimson. Pretty expensive tho

You can always build a jungle biome. Get a few hundred mud, add one jungle grass seed, and wait. Eventually you will have a jungle. Put it somewhere safe, or safer.

A few hundred mud is not enough to rebuild an underground jungle. I'd need a few thousand for that.

Who cares where it is. :P If you have a jungle, you have jungle resources.

Well, but if I have a small jungle, then farming chlorophyte is going to take years. :P

oh yeah :P

Couldn't you just travel to another world that *has* a decent sized jungle and farm it there?

Bit of a hassle, since it needs to be triggered in a hardmode world by defeating the wall of flesh and then all three mechanical bosses (after you've farmed the materials needed to craft their respective summoning items). And even then there won't be a lot because it slowly spreads over time.

Once you start getting chlorophyte, the jungle can recover lost ground since chlorophyte will turn nearby dirt and corrupt/crimson/normal grass into mud. Mine the chlorophyte that's in the center of the jungle, and leave chlorophyte near the corrupted areas so that they can push back against the corruption.

It's been my experience that chlorophyte does a pretty mediocre job of halting the corruption. It can, at best, create a stalemate with a corrupted area. I've never seen chlorophyte actually reclaim a corrupted area, probably because chlorophyte has maximum density limits and corruption doesn't.

Incoming wall of text:


My actual solution is to create corruption barriers around the worldgen biomes before entering hardmode. This is usually done by making a 5-width tunnels all the way around its edges. (You technically only need a 3-wide gap, but making it 5-wide prevents it from jumping across corners and gives you a bit of a buffer if you mess up.) I find that to be much easier than doing any shenanigans with the Clentaminator, plus you get to keep your biome for materials. You might need to be careful about corrupted grass, though, since the vines that dangle from the ceiling and the thorny vines that grow from the floor can both spread the corruption. If you've got a Drill Containment Unit, this process takes less than five minutes. If you don't, it takes a bit of time.

The REAL danger to the jungle comes from the diagonal columns of hallow and corruption that spawn when the WoF is defeated. Since these have some variation in where they spawn, I normally just back up my worldsave before killing the WoF, save and exit after he's dead and I get the announcement of light and dark, and check it in a world viewer. If the corrupted column goes right through my jungle, I'll reload and kill the WoF again. Note that the hallow going through the jungle is perfectly fine because hallow can't affect mud at all, but it means you probably won't have much surface hallow which will make getting unicorn horns and pixie dust harder.

Once the columns are in acceptable positions, I dig four more barriers, one on each side of both columns, again 5-width at the edges. If you do this immediately after the WoF is defeated, the lines will be very well-defined and you can preserve your cavern layer with (relatively) minimal effort. Note that this is significantly more time-consuming and dangerous than the pre-hardmode barriers, even with a Drill Containment Unit, because you'll be undergeared at that point. The longer you spend gearing up before doing this, however, the harder it will get, because the irregularities of the underground will cause the corruption to spread out unevenly, so you won't have the nice clean diagonals. On the bright side, you should have a good supply of souls and cursed flames or ichor once you're done, and that can really help later on.

In conclusion, it's a lot of work, but it is absolutely worth it. You get to preserve and separate all of the biomes, and retain control over your world. Since Terraria is all about manipulating the world to your benefit, it seems to me like a very worthwhile task.

You can't really account for or predict the corruption/hallow that spawns when you break a shadow altar, unfortunately. You just have to be vigilant, or use a world viewer to find them after they've spread out enough to be noticeable on the map, then dig down and clentaminate them.

Warning: Incoming rant. :P

So I've ultimately resorted to opening the world in TEdit and removing corruption (by selecting large areas and changing all ebonstone to stone, all ebonsand to sand, etc) manually, except for some isolated part behind the dungeon.

I don't really care if that's cheating or not. Struggling against corruption was becoming an exhausting chore. Even with clentaminator, you'd need 2 platinum for the tool, 2-4 platinum for green solution and then would need to dig hellevators every 180 blocks to manually cleanse your world of corruption. That's not fun, that's dull and tiresome. Not to mention it's way too expensive for something so essential - Clentaminator is the third most expensive item in the game, for Pete's sake, and the other two are freaking vanity items with no gameplay value whatsoever.

I'd still love some mod that would stop corruption, crimson and hallow from spreading by itself altogether, for future worlds. The initial V stripe that is created upon the world entering hardmode would be absolutely enough for me: it would create underground hallow and underground crimson/corruption to enable new enemies and souls farming and that's it. No significant world ruining.

Eh, why haven't you added an option to disable biome spread, ReLogic, WHY?! :(

First time through, when you don't understand the spread mechanism and speed, it's a real problem. I didn't buy the Clentaminator, nor did I edit the world, I just slogged through, thinking of things that I'd do differently. Mostly, that's just slicing things up, and lining at least one side of hellavators and tunnels with 1 layer of mushroom.

Anymore, I don't really care about the jungle. Clear out an area of all blocks in the caverns level straight down a hellavator from your base (pretty easy with the high-end pickaxes, though easy enough to do in about a half hour with the Reaver) then place blocks 3x5 or 4x4 of mud widely separated. Replace a single block in the middle with chlorophyte. A few screensful will let you farm chlorophyte in safety, and quickly enough that you can hardly shoot all the chloro bullets you want.

And jungle is awfully dangerous place to run around looking for lifefruit and spawning Planteras. Just lay down a single row of mud several screens long (caverns under base), put a seed or 6, then after it becomes jungle grass, replace every third block with a mushroom. (So you have a long run of mud, mud, mushroom, mud, mud, mushroom, etc.) This keeps away the 2x3 weeds that so quickly prevent lifefruit, and is a good place to spawn Planteras.

I do like to use mushrooms on the terrain to stop spread of corruption/crimson.

Oh, and don't break any more altars than you absolutely have to. Rely on fishing for most of your hardmode metal.