File:Lowest bedrock generation in an extreme Custom world.png

Summary
The terrain generator can place bedrock as low as Y=−2048 in Custom worlds with extended min_y. Custom settings used: {	"bonus_chest": false, "dimensions": { "minecraft:overworld": { "type": { "logical_height": 2368, "infiniburn": "minecraft:infiniburn_overworld", "effects": "minecraft:overworld", "ambient_light": 0.0, "respawn_anchor_works": false, "has_raids": true, "min_y": -2048, "height": 2368, "natural": true, "coordinate_scale": 1.0, "piglin_safe": false, "bed_works": true, "has_skylight": true, "has_ceiling": false, "ultrawarm": false },			"generator": { "biome_source": { "seed": 1, "large_biomes": false, "type": "minecraft:vanilla_layered" },				"seed": 1, "settings": { "aquifers_enabled": true, "noise_caves_enabled": true, "deepslate_enabled": true, "bedrock_floor_position": 0, "sea_level": 63, "disable_mob_generation": false, "default_block": { "Name": "minecraft:stone" },					"default_fluid": { "Properties": { "level": "0" },						"Name": "minecraft:water" },					"bedrock_roof_position": -2147483648, "structures": { "stronghold": { "distance": 32, "spread": 3, "count": 128 },						"structures": { "minecraft:fortress": { "spacing": 27, "separation": 4, "salt": 30084232 },							"minecraft:swamp_hut": { "spacing": 32, "separation": 8, "salt": 14357620 },							"minecraft:ocean_ruin": { "spacing": 20, "separation": 8, "salt": 14357621 },							"minecraft:village": { "spacing": 32, "separation": 8, "salt": 10387312 },							"minecraft:desert_pyramid": { "spacing": 32, "separation": 8, "salt": 14357617 },							"minecraft:bastion_remnant": { "spacing": 27, "separation": 4, "salt": 30084232 },							"minecraft:shipwreck": { "spacing": 24, "separation": 4, "salt": 165745295 },							"minecraft:pillager_outpost": { "spacing": 32, "separation": 8, "salt": 165745296 },							"minecraft:ruined_portal": { "spacing": 40, "separation": 15, "salt": 34222645 },							"minecraft:buried_treasure": { "spacing": 1, "separation": 0, "salt": 0 },							"minecraft:jungle_pyramid": { "spacing": 32, "separation": 8, "salt": 14357619 },							"minecraft:igloo": { "spacing": 32, "separation": 8, "salt": 14357618 },							"minecraft:stronghold": { "spacing": 1, "separation": 0, "salt": 0 },							"minecraft:nether_fossil": { "spacing": 2, "separation": 1, "salt": 14357921 },							"minecraft:mansion": { "spacing": 80, "separation": 20, "salt": 10387319 },							"minecraft:endcity": { "spacing": 20, "separation": 11, "salt": 10387313 },							"minecraft:mineshaft": { "spacing": 1, "separation": 0, "salt": 0 },							"minecraft:monument": { "spacing": 32, "separation": 5, "salt": 10387313 }						}					},					"noise": { "simplex_surface_noise": true, "random_density_offset": true, "size_vertical": 2, "density_factor": 1.0, "density_offset": -0.46875, "top_slide": { "target": -10, "size": 3, "offset": 0 },						"bottom_slide": { "target": 15, "size": 3, "offset": 0 },						"size_horizontal": 1, "min_y": -2048, "height": 2368, "sampling": { "xz_scale": 0.9999999814507745, "y_scale": 0.9999999814507745, "xz_factor": 80.0, "y_factor": 160.0 }					}				},				"type": "minecraft:noise" }		},		"minecraft:the_nether": { "type": "minecraft:the_nether", "generator": { "biome_source": { "preset": "minecraft:nether", "seed": 1, "type": "minecraft:multi_noise" },				"seed": 1, "settings": "minecraft:nether", "type": "minecraft:noise" }		},		"minecraft:the_end": { "type": "minecraft:the_end", "generator": { "biome_source": { "seed": 1, "type": "minecraft:the_end" },				"seed": 1, "settings": "minecraft:end", "type": "minecraft:noise" }		}	},	"seed": 1, "generate_features": true }