# Mana

Every spell, circle and gadget runs on mana. You carry some in your own pool, you store more in Mana Gems, and the
circles you build spend it by themselves.

## Your pool

You have a personal pool. New players get 2000 (`player_pool_cap`). It refills completely when you wake up from a
bed, and again when you respawn after dying.

Mana Gems hold much more. A new gem holds 100,000 (`gem_capacity`). Gems you carry, loose in your inventory or in a
bag without the network feature, top your pool up whenever it has room, and they pay for your casts directly when the pool runs dry.

The command `/ik mana` shows your pool, the charge in your gems and the total.

Opening the casting screen costs 100 mana (`cast_open_cost`). A spell cast from your own screen is paid from your
pool and the gems you carry, nowhere else.

## Where circles get theirs

Circles do not touch your pool. A circle you have drawn takes its mana from your **network**, in this order.

1. Black Hole twins, if you own them. They hold a balance with no practical limit.
2. Gems in chests that carry a STORE circle of yours.
3. Gems in pedestals that carry a STORE circle of yours.
4. Gems in your bags with the network feature, while you are online and in the same dimension.

If the network is dry, the circle goes dark. The exception is STORE circles themselves. They fall back to your own pool
and carried gems, so you can bootstrap a network from nothing. See [Storage]($mechanics/storage).

Mana that circles earn goes back into the same network, into your bags first and the twins last.

## What things cost

Circles have three kinds of cost, set per level in each circle's table.

| Cost | When you pay it |
|---|---|
| Cast | When you make the circle, and each time a CAD fires it |
| Upkeep | Every batch, for as long as the circle stands |
| Working | Every batch in which the circle is actually doing its job |

A batch is one second by default (`batch_ticks`, 20 ticks). A circle with no mana left stops working until its network
has some again.

`mana_cast_percent`, `mana_upkeep_percent` and `mana_working_percent` scale every circle's costs at once.

### Philosopher's Stone rebates

The best Philosopher's Stone you carry makes everything cheaper. The higher the grade, the bigger the discount.

| Grade | Casting and working | Upkeep |
|---|---|---|
| F | 5% off | 10% off |
| D | 10% off | 20% off |
| C | 15% off | 30% off |
| B | 20% off | 40% off |
| A | 25% off | 50% off |
| S | 30% off | 60% off |

Costs round up. The rebate follows the circle's owner. Servers can switch it off with `stone_rebate`.

## Pausing circles with redstone

A circle is paused while a redstone component next to the block it is drawn on powers that block, from any side. A
paused circle pays no upkeep and does no work.

- These pause a circle: a lever or button on the block, a redstone torch beside or under it, a repeater, comparator or
  observer pointing into it, and a redstone block against it.
- Plain redstone dust never does, and neither does an ordinary block that something else powers. Dust can run right
  past a circle.
- A circle that reads a redstone signal listens to the block on its own face. That block does not pause it.
- A paused STORE circle also drops out of the network, so its chest and gems stop counting until the signal goes.
- An RF Split circle ignores a free RF source beside it, such as a redstone block, because that is its fuel and not a
  switch. See [RF Bridge]($mechanics/rf_bridge).

## Where mana comes from

- **Pedestals.** A Mana Gem sitting on a pedestal charges itself every batch. It counts crops growing within 8 blocks
  (1 point each), living mobs in range (8 points each, undead excluded, and much more for mana-rich mobs such as
  endermen) and the biome around it (verdant biomes like jungle and swamp give 4, fertile ones like forest and plains
  give 1, barren ones nothing). One point is one mana. Every number can be changed with the `harvest_*` settings.
- **The RF bridge.** Turn Forge Energy into mana and back. See [RF Bridge]($mechanics/rf_bridge).
- **Crush.** Crushing blocks pays mana into your network by how hard they are.
- **Disenchant.** Stripping an enchantment pays mana into your network.
- **Pattern Blue.** What it digs up goes to your network, your bags and your pack. Anything on a void list, or that
  nothing has room for, is paid to you as mana by how hard it is.

Mana Blocks are the invisible blocks that chain circles together. See [Mana Blocks]($mechanics/mana_blocks).

Spending your last point of soul wipes your gems and your Stone. See [Soul]($mechanics/soul).