Why Minecraft says \"Too Expensive!\" — and the anvil order that avoids it
The prior-work penalty doubles every time you touch an anvil. Here is the rule behind it, and how to sequence combines so a full enchant set never hits the 40-level wall.
Every anvil combine stamps a hidden counter on the item called prior work penalty. It starts at 0, becomes 1 after the first combine, then 3, 7, 15, 31 — doubling and adding one each time. That penalty is added to the level cost in full, which is why a sword that cost 5 levels on Monday costs 35 on Friday.
Vanilla Java rejects any combine priced above 39 levels with Too Expensive!. So the goal is never "make each step cheap" — it is keep the tree shallow.
The rule that actually matters
Combining two items adds their penalties together and then increments. Two fresh books (penalty 0) merged into one book gives a book with penalty 1. Merge that into your sword and the sword carries the sum.
So the cheapest route is a balanced binary tree, not a chain:
bad sword + book1 + book2 + book3 + book4 (penalty 1, 3, 7, 15 …)
good (book1+book2) + (book3+book4) -> sword (penalty stays low on both sides)Practical sequence for a full-enchant tool
- Pair the books up before they ever touch the tool.
- Merge the pairs into two "super books".
- Merge those two into one.
- Apply that single book to the fresh, never-anvilled tool.
That is four combines instead of five, and the tool itself only ever gets penalised once.
Where the order still bites
- Repairing costs a combine too. Mending on the tool early means every repair is
free, but pre-Mending repairs each raise the penalty.
- Renaming counts. Naming the item at any point adds to the same counter — name it
last, or accept the cost.
- Bedrock differs. Bedrock caps the display at
Too Expensive!differently and
allows some combines Java refuses; the arithmetic below is Java Edition.
Rather than doing this on paper, put the item and the enchantments into the Enchantment Calculator — it searches the combine orders and returns the cheapest one, with the exact level cost at every step.