Fire with Fire, the successfully kickstarted online multiplayer tower defense game, has finally made itself available for free (well, free-to-play) to the action-strategy loving masses and can be downloaded, enjoyed and sampled over at Steam. It is still in Early Access and thus a project that's being actively developed, but also an already highly enjoyable, unique and polished offering.
Weird towers and cartoony graphics aside, Fire with Fire does also sport one on one competitive multiplayer which, surprising as it may sound for a TD game, works brilliantly. Just do bother with the extra registration step and you'll see that simultaneously destroying and guiding creeps is as enjoyable as it sounds.
Fire with Fire by Theory Georgiou, Brian Shepard and Stephen D. Gibson is available for Windows as free-to-play on Steam's Early Access.