Four transformations (四化)
Four marks the birth-year stem attaches to four stars — Wealth, Power, Fame, Obstruction.
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This engine example fixes a Jia birth-year stem, lunar month 1 day 15 and the Zi hour. Hua Lu attaches to Lian Zhen, Hua Quan to Po Jun, Hua Ke to Wu Qu and Hua Ji to Tai Yang. Each mark follows its star into the palace where that star is placed.
The small radiant star is the star receiving a transformation; the distinct shape beside it identifies Lu, Quan, Ke or Ji. Dim cells are palaces without one of these four marks in this example.
This is an example layout, not a personal chart or a current-year reading. The four marks are not a good-to-bad ranking. Hua Ji is not a prediction of misfortune, and assignments can vary with the selected transformation lineage.
Stars in this example
Read the four transformations
The four transformations are marks that the heavenly stem of the birth year attaches to four particular stars. Wealth (祿) is read as gain and flow, Power (權) as force and initiative, Fame (科) as name and recognition, Obstruction (忌) as blockage and fixation. The same star reads very differently once a transformation lands on it, so practitioners use them as the first handle for reading a chart. ⚠️ Convention does not read Obstruction as simply bad — fixation is also absorption. Which star receives which mark for a given stem differs in part between lineages, so another source may assign different transformations.
Source: reviewed Ziwei glossary and MYEONG's default transformation and main-star tables.