Gold, merchants, re-rolls and the pit in 9 Kings

Gold comes from 9 gold after every battle, 9 gold for every card thrown into the pit, and from cards such as Vault, Palace and Midas Touch. You spend it on merchant cards (30 gold, then 15 more for each extra card at the same visit), on re-rolls (10 gold, then 10 more each time) and on gold-cost cards such as Over-invest.

Income

Source	Gold
Any battle, won or lost	9
Card thrown into the pit	9 per card; Spare Change also gives 9
Vault	3 per Vault level every year; levels itself automatically
Palace (Greed base)	Golden enemies hit by its ray drop gold
Midas Touch	2% chance per stack to earn gold on a kill
Scapegoat (Rainbow)	3 gold per level when killed in battle
Mortgage	Destroys a plot for gold by its level
Loan decree	9 gold times the current year
Salvage decree	Pit gives triple gold

Spending

• Merchant. Three visits per run (years 7, 19 and 31). Each offers 6 cards of one type: the Jack of Structures (buildings and towers, plus your base), the Jack of Magic (tomes and enchantments) and the Jack of Arms (troops). The first purchase costs 30 gold and each further card at the same visit 15 more. Since Patch #27 you can re-roll which merchant type you are buying from.
• Re-rolls. Re-rolling loot, a merchant’s stock, the attacking king or a diplomat’s choice costs 10 gold and rises by 10 with each re-roll. Re-roll prices persist through the run: the increase does not reset at the next event. Free re-rolls come from Outsourcing (9), Persistent (+2 per rank) and Stubborn.
• Gold-cost cards. Over-invest spends 30 gold to raise every stat of a plot; Chaos Over-invest spends 999.

The pit

The pit (drawn as a well beside your kingdom) takes any card from your hand. Besides the 9 gold, several cards trigger on it:

Card or decree	Effect when a card goes into the pit
Oblation (Blood)	Thrown in itself: every troop gets units; grows by 1 for each earlier pit card
Recycler (Progress)	Adjacent plots get +2% damage and HP per level
Rewind (Time)	Thrown in: replaces your hand with copies of your last played cards
Death Pool	Gives a Sacrifice card for each card thrown in
Repurpose (1.0)	Trash cards trigger pit effects one more time
Wishing Well	Copies of the next card you throw in

Trash cards (Piece of Trash, Broken Cabulator, Bone Pile, Temp Null and others) exist mostly to be thrown in. King of Recycling asks for 9 pit cards in one run; Meh, Whatever asks you to throw your whole hand in during year 33.

Greed cards that scale with gold

• Mercenary: 1 unit for each 9 gold you hold, so spending gold shrinks the plot unless Servitude is active.
• Dispenser: gains attack speed for each gold you earn.
• Golden Hour (1.0): every gold gain in battle fires a Palace beam that deals damage equal to your current gold.
• Rebound (Rainbow): reaching 0 gold gives 99.

Gold achievements

Achievement	Requirement	Global rate
Cheapskate	Save 999+ gold in a single run	51.2%
Sir Spends-a-Lot	Buy 9 cards in a single run	59.6%
One Dollar Short	Reach a merchant with exactly 29 gold, one short of a card	16.8%
Spoiled	Pay 999+ gold for one re-roll	3.9%
Rake It In (1.0)	Get 999 gold in a single turn	new

Spoiled needs the re-roll price itself to pass 999, which takes about 100 re-rolls in one run because the price only climbs by 10. Players spread them across loot, merchant and attacker re-rolls during a long, gold-rich run; see hard achievements.