Wither Spawns when placing 2 t's of soul sand next to each other, with 4 Wither Skeleton Skulls
If you put 3 wither skeleton skulls next to each other, then place a t of soul sand under them AND 3 blocks to the right, the 4th head you place will trigger the wither spawning.
S=Soul sand
H=Head
1=1st
2=2nd
etc
H1 H1 H1 H3
S2 S2 S2 S1 S1 S1 =Wither Spawning
S2 S1 This graphic may view better on desktop
I have uploaded a YouTube video detailing what happened, it is possible to replicate it. Works for North and East, but not South nor West. I will upload both a screenshot of Before/After and the video aforementioned. It spawns the wither, when it should not. It seems to spawn in-between the two T's of Soul Sand, but the first patch is destroyed, so it is hard to tell.
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