Regarding this line on the template:

{{#if: {{{1|}}} |The Knights armor is created with four pieces of clothing which|The {{PAGENAME}} is one of four items for the Knight set of clothing, which when combined with the 3 other items,}}

The "#if" (called a parser function) is made especially for the knights armor page, which is a combination of all four items and has to have a slightly different introduction.

This #if line says if there is an entry {{knight|1}} then add the first line (as shown on Knights Armor):

The Knights armor is created with four pieces of clothing which

... otherwise, if there is only {{knight}} just add the second line (which is on all 4 knights items pages):

The {{PAGENAME}} is one of four items for the Knight set of clothing, which when combined with the 3 other items,
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