"Ice Spy" by Ruinae Retroque Rursus, a custom level for Manic Miners based on the level of the same name from LEGO Rock Raiders.
Objectives: Collect 25 crystals
Size: 56x56
Ice Spy
Contains no heightmap, which admittedly was one of the things that made Ice Spy unique. Collect 25 Energy Crystals.
If this level isn't the same as you remember I have reasonably extensively moved the crystals around - there are now a lot more crystals closer to home, something difficult in the original Ice Spy. There's also a Recharge Seam.
Also, shameless plug that this was made with my convetor. Heightmap and crystal support coming soon (tm)