Create a Cube → Simulation Tag → Soft Body
Make the cube floating around but not fall:
→ Simulate → Force → Attractor → Mode: Force, Strength: 100000, speed limit: 200cm
In Soft body → Force tag, drag Attractor in Force list box, Force mode: Include
Put Attractor in new created null (Alt+G by select Attractor layer) → in Null, R click to Animation rag → Vibrate →
in Vibrate menu, Tag → tick Enable Position, Amplitude: 100,100,100cm ; Frequency: 1
Make the floating more steady:
Back to Soft body tag, Force → Follow Position: 1; Follow Rotation: 10
Create smash cubes fall on big cube:
Duplicate Cube to top, scale down (delete soft body tag on new cube) → duplicate 1 more cube, group 2 cubes in null (Alt G again), rename as Falling → Simulation tag → Rigid Body →
In Collision tag,
Inherit tag: Apply Tag to Children, Individual Element: Off; Bounce 50%, Friction 30%
→
Force tag → Exclude mode, drag Attractor in List
Create damage effect upon collision (cube strong enough but only deform upon hitting) :
In big Cube, Object → Segment XYZ to all 12 →
Soft Body tag → Soft Body → Shape Conversation, Stiffness: 400, Elastic Limit: 1cm
In small cubes null, Rigid body tag → Mass → Use: Custom Mass, Mass change to 4 (larger value makes cubes heavier to hit on a stronger damage)
Back to big Cube layer → Parent Subdivision surface over the cube (make the cube smoother)
→
Soft Body tag → Soft Body → increase back Elastic limit, e.g. 4 (if the hitting too strong that deform the big cube out of shape)