Doesn't it just freeze the fluid surface below it? Like a puddle of blood that will turn to ice, or a thrown water source. I have not yet used it to not freeze the surface, but I always thought it needs a surface already, before it can ice the ground.
Nope, it can create a surface on anything, no liquid required. Same way Firebolt can create a fire surface on stone floors or just plain dirt (two things which are notoriously hard to burn). Cantrips shouldn't create surfaces at all honestly, it's a DOS2 gimmick and while it can be fun and make for interesting gameplay and strategies, it should be limited to higher tier spells like fireball, not starter cantrips.
