Read aloud as English 'M-P'. Native Chinese equivalent: 蓝 (lán, blue) or 蓝量 (lánliàng) / 蓝条 (lántiáo, mana bar) — derived from the standard blue mana bar in JRPG and MMO UIs. Gamers use both: MP是满的 = 蓝是满的. Compare HP / 血.
culture
Vocabulary inherited from Japanese RPGs (Final Fantasy, Dragon Quest) and early Western MMOs. Now appears in Chinese mobile games and is universally understood despite being Latin-letter abbreviation. 加蓝 (jiā lán, 'add blue') = restore MP.