User blog comment:Valeth/Assassin from "221-B"/@comment-32751919-20190925045057/@comment-27971189-20190925171943

Similar to Godslayer ver. of Colombus (remind me of Pirate of Carribean, pirates against 'god'), she also based on existing Servants, the Archer and Ruler. The idea is someone who counter both but also support unit to both as there's several interpretation of how she escape from England in "Scandal in Bohemia", by Moriarty help or by Sherlock help.

Locked card is normal card, her own card. Example how it works:

In Turn 1, you got A (her) - Q (her) - three others.

Use her NP and A for Arts Chain, if lucky, she kept her A, otherwise she kept Q for next turn.

If you use her NP again on following turn, card carried from previous turn not chosen again.

Actually, the wording is 'awkward' in her original concept (keep one of previous card), kinda glad Summer BB and Wikia define it into lock card. Surprisingly this idea works very well solving my design issue that is, how you make good Story Support to deal with Arthur (Alter) gimmick, moreover an Assassin (how many times you pick an Assassin for Story Support. LOL).