Mana beans are magical plants which produce pods similar to cocoa beans, but in current versions, they grow on the bottoms of logs. The first two stages are greenish, but later stages will show the color of their aspect.
They spawn on trees in Magical Forest biomes, and can only be grown in magical biomes (Magical Forest, Eerie, or even Tainted Land; other mods may provide other magical biomes). Naturally occurring mana bean pods will have one of the Primal Aspects (Aqua, Aer, Ignis, Ordo, Perditio, Terra), or Herba.
- Most importantly, mana beans can be distilled (or used in the crucible) to yield 1 point apiece of their aspect.
- When eaten, they give one research point of the respective aspect. So if you eat an Aqua bean, you obtain one Aqua research point.
- When Mana Beans are eaten, they cause a random status effect. In "pure" Thaumcraft, this is unlikely to be lethal, but other mods can add much more deadly status effects. In particular, Witchery enables Harming as an ongoing effect, which will be almost immediately lethal.
When planted on a log in a magical biome, the mana bean pod will slowly grow. In current versions, beans must be planted on the bottom of the log. (Any sort of wood will do, and the log's direction does not matter.)
When it reaches maturity, the mana bean pod will glow brightly with its aspect color, and magical vision will show its aspect. When harvested, the mature pod drops one or two mana beans. Mana pods have 4 levels of growth. Only the two largest stages can be harvested at all, and only a fully ripe pod drop more than one bean.
Mana beans now only spawn in the six primal aspects (plus Herba), but compound aspect mana beans can be created by growing beans of two different aspects next to each other.
When planted alone or next to beans of the same aspect, mana beans will grow into pods of the same aspect as the bean. However, when two beans of different aspects are planted next to each other, each has a chance to be "cross-pollinated" by the other. Mana Beans will only cross pollinate if they are grown adjacent to one another, that being any beans staggered in there arrangement will not cross pollinate. If the two aspects can form a compound, the cross-pollinated pod will be of that aspect, otherwise it will simply change to the other aspect. For example, if an Ordo and an Ignis bean are planted next to each other, either may become a Potentia bean. Over successive generations, this can be used to breed beans of any compound aspect. Attempting to grow beans through hybridization typically yields best results when beans are planted a-b-a-b etc... Using the last example, Ordo-Ignis-Ordo-Ignis in successive adjacent (not diagonal) blocks.
Mana beans grow very slowly, but use of a Lamp of Growth (or multiple such lamps) can help.
Formerly, mana beans grew on the sides of logs similarly to cocoa beans. The pods were always green, and the beans they dropped were of random aspects, including compound aspects. Their growth rate has also been nerfed several times.