---
name: blender-simulation-vfx
description: Build stable Blender 5.1+ simulations and effects. Use for rigid and soft bodies, cloth, fluid or smoke Mantaflow domains, particle and hair systems, collisions, caches, baking, renderable volumes, and simulation troubleshooting.
---

# Simulation and VFX

Treat simulation as a cached dependency graph, not a random button press. Freeze scale, transforms, collision thickness, frame range, gravity, and cache location before tuning.

1. Define the physical story, units, target shot range, and collision participants.
2. Make a reduced-resolution proof with clear cache ownership and deterministic initial state.
3. Validate collision scale, normals, velocities, and forces before raising resolution/substeps.
4. Bake one layer at a time; invalidate/rebake whenever an upstream dependency changes.
5. Render representative frames and archive the cache or documented regeneration inputs with the `.blend`.

Load [physics-cloth-rigid.md](references/physics-cloth-rigid.md) for body/cloth workflows. Load [fluids-hair-volumes.md](references/fluids-hair-volumes.md) for Mantaflow, particle/hair systems, volumes, and cache strategy.

## MCP verification

Bake and inspect caches through `execute_blender_code`; verify modifier/cache
state in the returned dict. Representative frames need
`render_viewport_to_path` — simulation parameters alone do not prove motion.