Danish website Brixit posted images of the box art for two upcoming TMNT sets, 79102 Stealth Shell in Pursuit, above, and 79103 Turtle Lair Attack, below. Gonna take a wild guess and say Splinter will only be available through the Lair set.
![](https://www.fbtb.net/guide/sets/teenage-mutant-ninja-turtles/79103/79103_500.png)
Thanks to Anonymous Tipster for the tip.
via Smashing Bricks via Brixit