Hello,
I am a fresh beginner in the field of arduino, just recently finished the 12 beginner lessons. I am running an escape room in Norway and I am eager to find ways to use arduino in that context. First mission: how hard is it to make flashbulbs flicker in a creepy basement kind of way? Is it just running the code of an flickering led light and getting the arduino hooked up to a solid state relay and have the 230v input in that SSR with the arduino running the program? Or would I be wise to go for a 12V bulb (will that give enough light)? Or is this really not a beginner project at all?
Thank you in advance 
how hard is it to make flashbulbs flicker in a creepy basement kind of way?
A flashbulb, or a regular-old incandescent light bulb?
Is it just running the code of an flickering led light and getting the arduino hooked up to a solid state relay and have the 230v input in that SSR with the arduino running the program?
That will work great with a regular light bulb! Controlled dimming of 50/60Hz AC is trickier but on/off or flickering is super-easy!
Start with the [u]Blink Example[/u], and once that's working with your relay & light bulb, use the [u]random()[/u] function to randomize the on/off times. ...Maybe constrain the delays to between 0.1 second (100mS) and a few seconds, or whatever gives the desired effect.*
Or would I be wise to go for a 12V bulb (will that give enough light)? Or is this really not a beginner project at all?
230V is "easier", but of course more dangerous, especially if you are a beginner with electricity. 
...The relay provides (solid state or electro-mechanical) does provide 100% electrical isolation , so it's safe if you wire it correctly and insulate/isolate the power line voltage so nobody can touch it.
You can't directly drive a 12V light bulb with the Arduino, so you'd still need a relay (or driver circuit) and you'd need a 12V power supply with enough current capability.
- You can "flash-on" a light bulb for about 1/10th of a second and it will reach nearly-full brightness. But if it's continuously-on and except you turn it off for 1/10th of a second, that's not as noticeable. I think the filament heats-up faster than it cools-off, but human perception may be a factor too.
Low-voltage LED lights can be very very bright nowadays (a 10W LED is about as bright as 80W incandescent or 15-20W fluorescent), and are much easier to switch: can be done electronically (MOSFET), so no wear and tear (like a relay) and much faster switching. So you can also get much shorter flashes.
Incandescents are much slower in flashing, and the frequent switching on and off often is probably pretty destructive for them.
Thank you so much for the respons DVDdoug! And yes I meant normal light bulbs On a youtube video it seemed to be pretty safe with the right relay and done correctly, but I will definitely get someone more experienced to go over it before I implement it in a room. I can't wait to try this now
Ooh and thank you Wvmarle, I will check out the low-voltage LED lights, what kind of bulb was actually the next thing I was trying to find out. And even if I don't understand the MOSFET, I will try to read up on it before I ask more questions
Try to find the clear glass bulbs with straight wire filaments. Bulbs with coiled wire filaments will vibrate due to the magnetic field changes when the power is off/on and will die sooner.
Paul