Mokou lost her Cards 滅罪「正直者の死」 - Forgiveness 'Honest Man's Death and/or 時効「月のいはかさの呪い」 - Limiting Edict 'Curse of Tsuki-no-Iwakasa' because Nitori changed destiny so that in the new history Mokou didn't kill Iwasaka (the man who was supposed to destroy the Hourai Elixir and was murdered by her in canon, as evidenced in Cage in Lunatic Runagate) and thus she didn't have a motivation to ever create the spells in the first place. [/infodump] Just in case anyone was wondering
Hmph...that by actions of this kappa...
(originally あの河童の行動で)SurprisedThat means...
(originally と、いうことはまさか。。。)Her effect was nullified...?
(originally その効力が消えて白紙化。。。?)A spell card is a symbol of those who use it.
(originally スペルカードはそれを使う者の象徴)...something about this girl was changed!
(originally 彼女にまつわる何かが変わった、ということか!)It means, that if everything is to be left as is...
(originally だってすれば、果たしてこのまま放置して良いことか)...this may adversely affect Gensokyo.
(originally この事が、幻想郷に悪影響を与えて可能性は)