Decay is the symptom of an unstable age. Decay manifests as a simple block, with the approximate toughness of
Decay block

A Decay Block.

dirt. Decay blocks quickly spread horizontally and down. Decay blocks will replace other blocks including Obsidian and Bedrock when they spread, but they do not spread to air. Occasionally, Decay blocks will replace the block below them and cause all blocks directly above them to drop as well. When a Decay block drops into the void, all blocks directly above it will fall into the void as well. Blocks will occasionally explode and even set on fire upon shifting.


Decay crater

A crater caused by decay blocks.

Decay blocks are soft and easy to destroy, but players often have no idea of their presence until it is too late. Warning signs such as growing craters serve to inform the player of their plight. Soon small indents in the terrain will become holes that go all the way to the void. These craters will eventually spread to the entire age and destroy nearly all blocks that exist in that age.

Floating blocks will not be affected by decay occurring beneath them, so safe platforms may be constructed by quick thinking players. However, the usefulness of safe platforms on otherwise destroyed ages is debatable.

Players who are worried about others wandering about their ages
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Safe platform, untouched by decay. Scarcity of resources makes it pointless, though.

unsupervised can put unstable books on display, possibly even with enticing labels meant to tempt over-greedy explorers. These makeshift trap books ensure that those with ill intentions are trapped until the player decides to rescue them.

In the event that decay is found, players are advised to vacate the age, as players who die in an age will respawn on that same age, and if there is no safe ground to spawn on, they will be unable to recover.

Types of Decay

There are currently 3 different types of decay, these are Black, Coloured and White Decay.

Black decay will begin to gobble up the age once it reaches void level. Black decay spreads down and to the sides; every time it spreads down, the connected blocks above it fall similarly to gravel. Hence, the blocks fall out of the world when the decay reaches the bottom of the terrain. Decay cannot spread through air; it needs adjacent blocks. It is possible to create safe floating platforms above the ground that will not be effected by black decay, but the usefulness of this is debatable when the rest of the Age is being destroyed.

Coloured decay doesn't eat the world but renders the world essentially useless because eventually all blocks placed will turn into decay blocks and you wont be able to collect resources from that age, this kind of decay comes in 3 different colours Blue, Red and Purple.

White Decay does damage to your player (0.5 heart/sec) making the world just as uninhabitable as it would with black decay due to your character dying if you don't take regeneration potions to balance out the effects of the damage. White decay is arguably even more dangerous than Black Decay, as it spreads in all directions, and even through air; guaranteeing that the entire Age will be destroyed eventually.

Stopping Decay

If small surface patches of decay are found, players can dig out the Decay blocks by hand or with a shovel. However, simply stopping one pocket of decay will not stop other pockets from growing, all decay must be dealt with in order to stabilize an age. This is nearly impossible by hand.

The ability to re-write books in order to stabilize them is planned, with players able to cross out symbols that add instability or write in symbols that remove instability. However, this will lead to the world changing when players revisit it. Small changes will be possible while preserving player made structures and alterations. Large changes however, will cause the original link to be broken and a new link established, and the rewritten age will not show any signs of previous player interaction.

Outside of game, Decay can be disabled by setting the options.decay property to false in the mystcraft_config.txt file found in the .techniclauncher\technicssp\config directory for Technic 7.2.6.

Testing for Decay

A simple way to test for decay is to fill up suspicious spots with blocks until the surface is level. Any change can be attributed to decay.


Without decay on.


With decay on.

Decay can cause lag when combined with another Java using player (EX. YouTube). Massive amounts of lag is a great way to know if there is decay.

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