English (Source)
Opens a menu with different ranks which you can promote a tower to, giving them one of the following buffs depending on which rank they were promoted to:
Disciple: <Keyword>EBuffType::ENLIST_RECRUIT</>
Invoker: <Keyword>EBuffType::ENLIST_VETERAN</>
Sharpshooter: <Keyword>EBuffType::ENLIST_SPECIALIST</>
Berserker: <Keyword>EBuffType::ENLIST_COMMANDER</>
Oppressor: <Keyword>EBuffType::ENLIST_OPPRESSOR</>
Japanese Translation
タワーを昇格できる複数のランクのメニューを開く。昇格先のランクに応じて、以下のいずれかのバフを付与する：
弟子：<Keyword>EBuffType::ENLIST_RECRUIT</>
呪文使い：<Keyword>EBuffType::ENLIST_VETERAN</>
名射手：<Keyword>EBuffType::ENLIST_SPECIALIST</>
バーサーカー：<Keyword>EBuffType::ENLIST_COMMANDER</>
オプレッサー：<Keyword>EBuffType::ENLIST_OPPRESSOR</>