Talk:Hard Mode/@comment-34210303-20180105122402/@comment-26440657-20180105125950

If your entire world is already changed then it's not worth it. If you start a new world and want to know how to cure the whole world then use a Clentaminator. If you just want to contain them then dig a trench of at least 4-6 tiles wide around all infectious biomes and fill it with rope if you feel there's a chance vines will bridge the gap (only happens for blocks with grass).

As a safety precaution, dig a hellevator every 110 blocks to make sure your world won't get contaminated. 110 because a clentaminator has a range of 60 blocks.

Another thing to note is that each altar you break spawns a single piece of infected block in a random part of the world, so don't break too many, it is possible to not break any at all and still get ores by fishing for crates and opening them when hardmode starts so they can drop hardmode ores. I never need to break altars, I fish a lot before hardmode even starts and open crates as soon as hardmode arrives.