The spelling of the word "vagan" may seem confusing, but it follows the rules of English phonetics. The initial letter "v" is pronounced as a voiced labiodental fricative sound /v/. The following letter "a" is pronounced as a short vowel sound /æ/. The letter "g" is pronounced as a voiced velar stop sound /ɡ/. The letter "a" is pronounced again as a short vowel sound /æ/. The final letter "n" is pronounced as a voiced alveolar nasal sound /n/. Therefore, the correct IPA transcription of "vagan" is /væɡæn/.