Fencer, your idea of "Would you dare to win Espionage by capturing opponent's base without revealing it by a spy?" is good but rather easy. Just capture it with a sab! Perhaps modify the achievement to "Would you dare to win Espionage by capturing the opponent's base with a 4 or 5 without revealing it with a spy?"
(Cacher) Si vous voulez trouver un adversaire avec un niveau de jeu identique au vôtre, regardez la page des Classements du type de jeu que vous souhaitez et trouvez un joueur ayant un même BKR. (pauloaguia) (Montrer toutes les astuces)