SPF lumber from the local big box store would be difficult to keep straight and square the larger the piece. Most of the wood has a fairly high moisture content to start with and I imagine moves quite a bit over time. Small Jenga pieces wouldn’t matter too much but the larger the piece the proportionally larger the movement. Would be fun to make this out of well dryed maple with a good wax coat on it.
Rob, Sault Ste. Marie, Ontario