The two BTS songs that have been displayed as an ambigram are "Spring Day" and "Blood Sweat & Tears." An ambigram is a design that can be read in more than one direction and still make sense. Both of these songs have been creatively designed to form an ambigram, which is a unique and interesting way to showcase the lyrics of the songs. Ambigrams are often used in branding, logos, and advertising to create a memorable and visually pleasing effect. Fans of BTS have praised the creative use of ambigrams in their music, which adds an extra layer of depth to their already meaningful lyrics.