Here's a collection of useful tools and other tricks of the trade for any aspiring DM. It includes affiliate links for all the campaign and rulebooks.
makeaskillcheck.com appears in the published seller files of 1 advertising network. Each row below is that network's own declaration that it is authorised to sell this site's inventory, with the date the relationship first appeared in the record.
Same niche, closest authority score — the competitive set a network would compare makeaskillcheck.com against.