Spells/Cast
Spells/Cast describes how many slots' worth of spells the wand casts in one action. A multicast spell can make multiple projectiles fire together.
How it works
The basics guide says the value is usually 1. Multicast groups spells so they are cast at once, and a modifier applied to the group affects all simultaneously cast spells. The sequence and grouping therefore matter when arranging a combined shot.
Your next step
Test how your multicast groups the following spells and modifiers.
Read the supporting references
Noita wand building, including wand stats, editing, and named spell choices supported by the supplied evidence. The evidence does not establish a specific patch or edition. Guidance explains the referenced mechanics; it is not a tested damage ranking. Check the stated edition and source version before applying a patch-specific detail.