A while ago I made this thread: AHC: Muslim-majority Indochina. It gained quite some traction and interest before eventually dying off, which motivated to me to try something more unique. The objective of this AHC is once again to make Indochina a firmly Islamic region, but with a twist: Maritime Southeast Asia may not convert, and should remain Hindu-Buddhist. Essentially, we're switching the fates of the two parts of SEA around, as IOTL Maritime SEA Islamized and Indochina remained Hindu-Buddhist.
- Malaya may convert, on the basis of being part of Mainland Southeast Asia, as long as Indonesia, Brunei, Sarawak and Sabah don't. However, bonus points are awarded if the Malays do not convert to Islam (this'll make the AHC more challenging, too, as Malay traders faciliated the spread of Islam in Indonesia and were brought up in my previous thread as a way of converting Indochina as well).
- Vietnam is part of Indochina, even if it's far less influenced by Hindu-Buddhism / India and instead leans more towards China. Hence, the conversion of Vietnam to Islam is necessary.
- The Philippines may become Christianized by the arrival of the Spaniards, but avoiding this also nets you bonus points. The Muslim sultanates in the south (e.g. Sulu, Mindanao) may not be established.
- Srivijaya or Majapahit may be saved, but you can also still make them collapse. As long as Maritime SEA feasibly remains Hindu-Buddhist, you can do whatever with these two.
- I'm aware that Maritime SEA largely practiced Hindu-Buddhist-influenced animism, with the real deal mainly being for the elite (so no real need to bring up that Reddit post again, as helpful as it is). I'm sure you get the point of this thread, though. If you can make the common people of Maritime SEA practice Hinduism and / or Buddhism, though, you also get a bonus point.