hello, i want to stick the small spheres to the TIP of those spikes. i completely created the main object via geo nodes. so in the end i want to place the spheres at the TOP of the final extrusion (spikes), and when ii change the value of the length of the spikes, the spheres should move with them, as if they are glued to the tips of the spikes.
i was able to create that via a vertex group after applying the geo nodes modifyer, but then i lose a lot of control over the spikes, so ii want to KEEP the control inside the node tree.
any ideas how to tell the spheres that their location should ALWAYS be the tip of those spikes (no matter how i change them later)? thx
thanks for your help! very much appreciated! 
i will try the solution and let you know!
i use the first random value to control how many extrusions overall will appear on the main surface, i was not sure if i want to keep all or reduce them later.
it works perfectly! thank you so much!
one question: i want to align the instances to the NORMAL-rotation of the respective points they are instanced to. in my example i used an “Euler to vector” node with a normal node plugged into the rotation value, but it doesn’t work anymore… do you have a fix for that?
The Normal is a Vector, not a Rotation - plug it into the Vector input instead and it should work.
Also, capture the Normal before the Mesh to Points node and use the captured value (Normals don’t exist on Points).
PERFECT! worked exactly as i needed! Thanks mate! 