Fallout transmutation · movblock.mov

File: data/hbm/hbm/fallout_table/default.json. Override hbm:default to replace the table.

{
  "rules": [
    {
      "targets": "#minecraft:mineable/pickaxe",
      "max_distance_percent": 50.0,
      "restrict_depth": true,
      "primary": [{"state": {"Name": "hbm:sellafield_slaked", "Properties": {"shade": "0"}}, "weight": 1}]
    }
  ]
}

A fallout cloud walks each column of its radius from the top down. For each block, the rules are tried in list order and the first that converts it wins; three restrict_depth conversions, or three solid blocks no rule converted, end the column.

Field	Meaning and default
`rules`	Ordered replacement rules; the first matching conversion wins.
`targets`Optional	Block ID, block tag, or ID list; default every block.
`state`Optional	Vanilla state-property predicate.
`must_be_opaque`Optional	Restricts matches to occluding blocks; default false.
`restrict_depth`Optional	Counts a conversion toward the column stop; default false.
`primary`Optional	Weighted outcomes when chance succeeds; default empty.
`secondary`Optional	Weighted outcomes when chance fails; default empty.
`primary[].state`	Block state placed by a primary outcome.
`primary[].weight`	Relative selection weight; positive total at most 2³¹−1. Range: 1 to 2³¹−1
`secondary[].state`	Block state placed by a secondary outcome.
`secondary[].weight`	Relative selection weight; positive total at most 2³¹−1. Range: 1 to 2³¹−1
`chance`Optional	Probability of drawing from primary; default 1.0. Range: 0–1 for a useful probability
`min_distance_percent`Optional	Inner distance bound; default 0. Range: 0–100 for a useful distance
`max_distance_percent`Optional	Outer distance bound; default 100; at least min_distance_percent. Range: 0–100 for a useful distance
`falloff_start`Optional	Fraction of the outer bound where conversions thin out; default 0.9. Range: 0–1 for a useful fraction
`preserve`Optional	State property names copied from the replaced block; default empty.

In 1.0.0, weighted selection favors earlier outcomes. With two outcomes of weight 1, the first is always selected.

The shipped rules use #minecraft:mineable/axe for wood, #minecraft:mineable/pickaxe for rock and metal, and #minecraft:mineable/shovel for sand and soil.