Here is the full list of all 27 Skulls of the Shogun achievements.
Have an emblem upgraded to Gold status.
Acquire your first "Very Rare" emblem.
Acquire 100 emblems.
Defeat a General with a Tanuki taunt.
Complete every level such that your best times for all of them add up to less than 4 hours on Normal difficulty.
Complete the Forbidden Islands on Normal difficulty.
Complete the Forbidden Islands with 10 units or more.
Earn all 72 of the Bone-A-Fide Edition Gold Skulls.
Knock 3 foes off a ledge at once with a Demon Crow Monk's Typhoon spell.
Complete the Land of Frozen Fortunes on Normal difficulty.
Earn 60 gold skulls.
Complete the Land of Golden Harvest on Normal difficulty.
Complete the Land of Monsoon Meadows on Normal difficulty.
Earn 30 gold skulls.
Defeat 5 foes at once with a Salamander Monk's Lightning Storm spell.
Complete the Land of Eternal Blossoms on Normal difficulty.
Win a team deathmatch game with your teammate still alive.
Break a Deadly Alliance in online multiplayer.
Win an online multiplayer match.
Win a 4-player online multiplayer match.
Win an online match that lasts at least 30 rounds, defeating at least 30 enemies.
Earn 15 gold skulls.
Defeat an enemy Monk by haunting its Shrine.
Bring back a fallen unit with a Demon Fox Monk's Revive spell.
Complete the Shores of the Dead on Normal difficulty.
Win a multiplayer match with a 20-second-per-turn time limit.
Power up your General to a Demon.