I have all the time in the world so
that doesn’t need taken into account.
Lucky. Still, I’d spawn them procedurally.
To be clear i will likely be putting
thousands of these terrain blocks into
the game but only 30 (absolute max) or
so will be visible at any one time
(top down camera).
HISMs then. Per instance culling. If you place 1000 but can only see 30, you only render 30.
Also, this excellent bit:
And HISMs got a couple of bugs ironed out in 4.26.