As experts of these games, we can advise people on the cards available, and. We should also aspire to advise players on how to find those cards for themselves: give them fish, but also teach them how to fish for themselves.
Many novice players don't know how to find cards effectively when there's a rare effect they need. Yu-Gi-Oh has a community-driven wiki with cards categorised by effects, and. Magic: the Gathering has common wording structures we can search by and multiple good search engines to use. As experts we're well-placed to advise on using these tools.
The questions we get asked tend to only have a very limited pool of options available. Players don't need our help finding fairly common effects, just rare stuff. This means there's usually only a fairly small number of cards available, sometimes even only one or two. We can direct people to the body of cards available that suit the purpose and guide them through their options. If there aren't any perfect fits, then we can advise on the pros/cons of the best-fitting options. If there's nothing at all that does that, we can advise them about that too.
- Suggest the full body of cards available that fit the qualities the querent is asking for, or at least, the fullest that can be readily described (if it's actually a large request). We're aiming for comprehensive or complete answers in this context.
- Walk the querent through how they'd find those cards themselves: teach them to fish.
- Where there are unusual fits (e, e.g. the cardsonly options come with catches or restrictions), advise on the options available.
- Where there's no fits for what the querent's looking for, tell them that. If they described what they were trying to accomplish, guide them to what they should be looking for to accomplish that instead. (E.G. hypothetically: "There's no cards that blink everything you have and all the counters on them in the event of a board wipe. Instead you should aim to make them indestructible, regeneration, or give them protection. Here's a search for the cards that do that, since there's a lot.")