The population of Sangan-e Olya is 171.
No
There are a few cards that will enable you to search for low level Spellcaster-type Monsters from your deck:"Apprentice Magician""Sangan""Witch of the Black Forest""Magician's Circle"also summoner monk
Reinforcement of the army:Add 1 Level 4 or lower Warrior-Type monster from your Deck to your hand. Its a spell card
No part of Call of the Haunted or Royal Decree affect a monster's ability to attack. The Sangan will be able to attack as normal.
Sanwitchis the Fusion monster made from Sangan and Witch of the Black Forest.
Yes, Sangan's mandatory trigger will activate after the monster is summoned.
Yes, Sangan has a Mandatory Trigger (so never misses the timing), and a tribute is a form of Send. If you tribute it for a tribute summon, Sangan will activate when the summon is successful, or if the summon is negated, after the resolution of the negation card. If you tribute it for a card effect such as Enemy Controller, then allow the chain to resolve. Sangan will start a new chain as chain link 1.
Sangan triggers in the graveyard, so it's irrelevant if it was face down or face up when it was destroyed. It will trigger in both cases.
the trap card -divine wrath-
Yes it can. Sangan is a triggered effect, Stardust Dragon Assault Mode can chain to and negate it.
"Metal Raiders", "Dark Beginning vol. 2", "Gold Series 2" and "Turbo Pack 6" are the booster packs that contained "Sangan". In the United States, it was also in the "Dark Legends" booster pack, and in Europe, "Sangan" was in the booster pack "Retro Pack 1".