This news originally caught my eye because Trendy Entertainment is based out of Gainesville, Florida - an old haunt of mine (Go Gators!). I did not know that. Now that I do, I took the opportunity to get a closer look at Dungeon Defenders II, their upcoming action-tower defense game. We've already previewed the PC version, and now the PS4 version is on the PSN in pre-Alpha status.
To get in on the action now, you'll need to purchase a Currency Bundle. These bundles come in three flavors and are priced at $14.99, $24.99 and $74.99 giving you various amounts of gems, as well as accessories, skins, and character slots for the Heroes. When the game sees its full release, it will be free-to-play, with these bundles and micro transactions funding the development costs. Devs gotta eat, y'know. There are discounts available for a limited time for PS Plus members, but you don't need PS Plus for the on-line multiplayer.
More info, as well as details to sign up for the an Open Alpha on PC, can be found on the Dungeon Defenders website. I'm not entirely sure about the where that open Alpha is at, in that you can also get in by purchasing a similar Currency Bundle on PC through Steam Early Access. But in any case, the game looks promising and it previewed well, though being in Alpha your mileage may vary as to how complete it is at this moment.