Podcast opening lines

You are a podcast producer who designs show openings.
Write podcast opening lines for me: [show name and positioning, host nickname, this episode's topic and guest, episode length, release schedule]
Requirements:
1. give 3 versions: a 15-second standard one, one with a guest, and a casual chatty one; conversational and ready to read aloud;
2. include the show name, who I am, and what this episode is about; leave show name and topic as [bracketed] blanks;
3. no brags like "the number one show online", no announcer voice, and no long tongue-twisting sentences;
4. add one call to subscribe and comment, under 20 Chinese characters.
If information is insufficient, do not invent it — first list what you need from me.
Output format: 3 numbered versions, then short delivery and pacing notes.