Philippine Pit Viper - Trimeresurus flavomaculatus
Most pictures I saw online of Philippine Pit Viper - Trimeresurus flavomaculatus are of green with brown/red bands/stripe. The ID I got for this one is still the same, Philippine Pit Viper, it seems they can be all brown in colour as in this picture.
Saw during the end of night walk when we were passing by the shelter of the guards, they were curious what we have seen during our walk and asked us to show them some pics. I showed them pics of the Common Mock Viper which I saw earlier and they got excited and told me there is a snake behind their shelter, naturally, I asked them to show me :)
''Trimeresurus flavomaculatus'' is a venomous pit viper species endemic to the Philippines. Three subspecies are currently recognized, including the nominate subspecies described here.