What is the default Starting Silk Road Innovations game rule in CK3?

Preset: Starting Silk Road Innovations will be the same preset selection in each bookmark. (patch 1.20.1.2)

Does changing the Starting Silk Road Innovations rule disable achievements?

No: none of its 2 settings carries the flag blocks_achievements in patch 1.20.1.2.

Game rule · Historicity

Starting Silk Road Innovations

Preset · default
Random

Starting Silk Road Innovations is a game rule in Crusader Kings III (Historicity) with 2 settings: Preset (the default) and Random. None of its settings disables achievements. Patch 1.20.1.2, from game/common/game_rules/00_game_rules.txt.

This section as JSON: /raw/game-rules.json

Quick answers (2)

What is the default Starting Silk Road Innovations game rule in CK3?: Preset: Starting Silk Road Innovations will be the same preset selection in each bookmark. (patch 1.20.1.2)
Does changing the Starting Silk Road Innovations rule disable achievements?: No: none of its 2 settings carries the flag blocks_achievements in patch 1.20.1.2.

2 settings

Preset
Default
Starting Silk Road Innovations will be the same preset selection in each bookmark.
silk_road_starting_innovations_preset
Random
Starting Silk Road Innovations will be randomly selected from possibilities of the Era.
The script checks it once, in 1 place
Events 1
- neutral_situation.0007
Every has_game_rule = silk_road_starting_innovations_random in game/common and game/events, by the top-level object it sits in.
silk_road_starting_innovations_random

Source: game/common/game_rules/00_game_rules.txt line 1608 (key silk_road_starting_innovations), modifiers from game/common/modifiers, names from the English localisation; Crusader Kings III 1.20.1.2.