It's played by connecting strings of adjoining letters to find words.
I don't want to lose this game if/when the MycenaCave goes offline for good.
There are many variants of this style of game, but I haven't found a singular unified term for this style of game, and yours is the only one comprised of pentagons that I've seen. Most I've seen are either squares, or the letters are in a circle and can be connected to any other letter.
I'd think they'd share a name with boggle or word searches, as they have similar play patterns and rulesets.