I'm making a board game with blocks, both made of thin plywood. I don't know what type of wood it is; (it is light in colour and weight and rather soft) I would like to coat the wood eventually (which will be pyrographed) for more strength and protection, but I don't know what would be suitable to use for the purpose (there is a wide variety of products and I'm not very well familiar with them).
It will be good if it doesn't emit toxic fumes but I need it to provide more protection that mere linseed oil. Shellac is not an option (due to high price and lack of availability).