In late 2011, Thomas reacquainted himself with the original Wolfenstein 3D, playing all six episodes using the new SDL technology, for the first time in more than eight years. Following this, he also played Spear of Destiny from beginning to end.
Not having grown up with Spear of Destiny, Thomas often had a hard time modifying the game. Though there had been numerous previous attempts at doing so, 2009's Hard Cell had been his only Spear-related project to see a release, and this was quickly withdrawn. These maps later appeared in Odds and Ends.
Initially envisioned as a pure Spear of Destiny map set, using the same set of rules as Thomas' Wolfenstein 3D, it instead turned into an experimental project using unorthodox selections of sprites, textures and overall level structure, though bosses and secret levels were left in place.
Mapping was done at an incredibly brisk pace, with most levels being finished around Christmas and New Year's 2011/2012.
Level 19 was an outtake from the then-upcoming Time to Kill, having been the first level made for that project. As Time to Kill was now his main point of attention, Thomas quickly wrapped up Spearfishwolfbones and released it on January 15, 2012. It was playable in both DOS and SDL, as only the maps had been altered.