Could you get 16 Efficiency 1 books and combine them to make an Efficiency 5 book?

It takes

• 2 lvl 1 books to make a lvl 2 book.
• 2 lvl 2 to make lvl 3.
• 2 lvl 3 to make lvl 4.
• 2 lvl 4 to make lvl 5.

So... 1 lvl 5 book = 2 lvl 4 = 4 lvl 3 = 8 lvl 2 = 16 lvl 1 books.

Could you then continuously combine 16 lvl 1 books up to get a lvl 5 book?

Or does the cost penalty increase like it does when repairing weapons/tools/armour?

Would it become "Too Expensive" before you got there?

Solution 1:

Yes, it is possible. I've tested this, and here are the results:

• Combining 16 Efficiency I books into 8 Efficiency II books: 2 levels each (16 levels)
• Combining these 8 books into 4 Efficiency III books: 5 levels each (20 levels)
• Combining these 4 books into 2 Efficiency IV books: 10 levels each (20 levels)
• Combining these 2 books into 1 Efficiency V book: 19 levels
• Applying this Efficiency V book onto an unenchanted diamond pickaxe: 20 levels

Even with prior work penalty, the highest individual level cost does not go above 20, which means that it is not only possible, but also reasonably achievable in a survival game. However, it costs a whopping 95 levels to fully enchant a tool using only Efficiency I books.

If you're dead set on using this method, combine the books as soon as you have the levels to do so. Since you level up a lot faster when you have low levels, it would take a lot less XP (and time) to combine books as you go than if you waited until you're level 95.