The words rampago and rayo are interjections in the Chabacano language. They both can mean 'damn it', 'darn it', 'damn', or 'darn'. Both of these I believe come from the Spanish relampago and rayos (respectively).
The words relampago and rayo in Spanish mean 'lightning' or 'a flash of lightning'. As far as the research I have done on the word relampago, it is never used as an interjection in the Spanish language. The interjection rayos (with an s) does occur in the Spanish language and it means 'damn' or 'damn it'. And because of the Chabacano accent wherein Chabacano speakers normally drop the 's' at the end of a word, we can safely assume that the Chabacano rayo came from the Spanish rayos.
This word also exists in the Chavacano de Ternate languagee. Esteban A De Ocampo, in his book, defines this word as 'ray', 'thunderbolt', and 'an insulting word or remark'. The word can also be spelled as rayu in the Chavacano de Ternate.
Other words that possibly originated from the Chabacano rampago are raman and rampet. Rampet is a fairly new word and probably was first used during the 1980s.
In the Chabacano dictionary of Rolando Arquiza Santos (2010), the words rampago, rayo, and raman are listed. Meanwhile, only the words rampago and raman are listed in the Chabacano dictionary of Camins.