Fake block to be used for stacking (ie elevation of other widgets/blocks) in order to save genuine (ie useful) blocks. Having more genuine blocks free allow to build more and longer funny tracks.

If classic blocks (blue, orange, transparent/white) can still be printed instead (some models available on the web) stacking block may save roughly 50% of material (eg PLA filament) and takes around 50% less time to print comparing to a normal block (tested : 13/14g vs 26/28g and 1h40 vs 3h15) depending on models and printing settings.

To assemble parts put the cross on base then upside down the whole then tap/push gently on the base to insert cross into the notchs.
It is recommanded to glue cross/spikes to base to strengh the whole.

You may need to handle with care when plug-in or plug-out to not break spikes. Depending material/filament used it may be hard to stack/plug out stacking blocks between them (especially for children) as printed layers add much more friction while genuine ones are much more slicker. If hard to stack try one of these :
o sand spikes and/or base for better fit
o do first stacking actions slowly until layers are more flatten
o alternate genuine and fake blocks (easiest solution, see picture)

Support needed
Base : Infill 20% or more
Cross : Infill > 80% (even 100%) recommended for pull-out strength

Changelog :
13-Oct-22 : v1 released