When building a board in Izu mode, I first look to discard items I consider weak relative to the others present. The Slingshot has niche usefulness and a maxed Jagged Saw is inferior to a maxed Vampiric Spear, so I ignore those items completely. It is worth noting that with the Jagged Saw you have a faster early game and the ability to leech exp to other squares easier, but I prefer late game strength over early speed in most boards.

 

I didn't find the right solution from the Internet.

 

References:

https://www.gamespot.com/forums/games-discussion-1000000/should-i-buy-dying-light-33395407/#8

 

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