"MOBILYS" is an instrumental trance track by Japanese composer Dachs, originally entered in the BMS of Fighters eXtreme Violence (BOFXV) song contest, where it placed 12th overall. The track is classified in the BMS scene as "Aesthetic Trance," a descriptor that signals its polished, atmospheric blend of hypnotic synth arpeggios and driving four-on-the-floor percussion. The accompanying BGA (background animation) was produced by the artist わっふゑ, giving the song a distinct visual identity from its contest days. In maimai, "MOBILYS" was added to でらっくす UNiVERSE on October 1, 2021, under the GAME & VARIETY category. The song also appears in two other rhythm games, Phigros (by Pigeon Games) and Sixtar Gate: STARTRAIL (by Lyrebird Studio), making it a minor cross-platform staple among fans of the competitive BMS-to-arcade pipeline. The MASTER chart, designed by はっぴー, is notable for its dense Touch-note layout (122 Touch notes out of 710 total), a distinctive design choice that gives the upper-difficulty play a tactile, sensor-driven character uncommon among 13-level charts of its era.