Instead of calling it "comedy", aim for humor. Humor that supports a key discovery helps to anchor that insight in the investor's mind.
I've coached many pitches, and find that when presenters are nervous they try to go for an improvised laugh, thinking it will cut the tension. However, in most situations, it comes off as just that: improvised and cheesy. Which confims to the audience that the presenter is nervous and unsure.
Humor an advanced communication skill which requires strategy, planning and practice. The best humor is subtle and smart. The goal is not to get a laugh, but to get a knowing smile.

The single biggest problem with pitch decks is that every investor wants something different in the deck. A deck is most useful at two points of the raise: To establish an initial meeting and, in the case of a VC firm, if the partner likes it, as the primary material they circulate to their partners to get internal buy-in.

Decks should be optimized to frame your company's opportunity in the simplest of terms, in the best of light, and presented in a fashion that carries the least amount of *perceptual risk.*

So for the primary reasons of looking to reduce perceptual risk and because each investor would reach so differently, I would avoid the use of comedy in your deck. The only exception to this rule is if you feel strongly that the inability to appreciate the comedy is indicative of the kind of investor you wouldn't take money from. In that case, you can do so, knowing that while your overall chances of success in raising might decrease, your chance of investing from a very particular type of investor might actually increase.

Happy to talk this through in more detail in a call if you'd like.

As someone who has sat on all sides of the table from entrepreneur to investor I can say that comedy can both seal the deal or kill the deal. Comedy is tough and delivery is everything. If the information resonates and creates an emotional moment with a positive response than you're good. Comedy should be relevant and informative to the pitch but be prepared to move on quickly if it is received with no response.

If you do add comedy to your pitch, I would recommend testing the delivery on a few close friends for feedback and then pick a few people from Clarity to share your pitch to get feedback on whether you should tweak the comedic element or ditch it altogether.

I recommend humour in pitches, but never in the deck. Great comedians feel the room and time their delivery. This is impossible in a deck. I am always reminded of my profs explaining the joke in the first slide of the first lecture..." you see it is funny because the student is saying..." That is a bad place to be in your pitch.

Of course, if you are pitching a comedy business, then comedy in the deck might be called for.

Make your deck smart and straightforward - fancy wordplay, double entendres, sarcasm and hokey punchlines do not scan for busy people looking to be impressed. Keep it to your presentation, and workshop any planned jokes thoroughly so you know they work (and you know how to deliver them easily). Also it should go without saying that risqué jokes can backfire and sexist/racist/homophibic jokes will backfire bigtime.

Personally, I would not use humor as you never know who is reading the deck. I suggest being succinct and to the point. The quicker to the point the better.

Good luck!

I reviewed a pitch deck that has a slide showing a greedy looking man kissing money bags with the title "We want your money not advise".

I found it funny with a serious message.

The deck itself needs to tell a story. If it is a new market that you are addressing, think about how to articulate its size and importance in a defensible way. Have a clearly articulated actual pain point that your product is solving and show evidence. Be focused on having a clear view of who is going to pay you for your product. Do not assume that people know your market in depth. As the leader of the business, you need to be the face and cannot outsource this. If you are showcasing your team, make sure it really is a showcase, not just an intro at the start. A simple chart could be very misleading and kill your credibility.
You can read more here: https://sifted.eu/articles/pitch-deck-tips/
Besides if you do have any questions give me a call: https://clarity.fm/joy-brotonath