Lmao! anyways love the spell it's a fun way to trick my players

Once you can cast 6th level spells you are required to go crazy with illusions. My illusionist warlock created a whole town that was mostly illusions.  The buildings were cheaply made just to keep wind/weather out and then covered with illusions of houses, a tavern, etc. Most important was the temple. It was a a shrine to his fiendish patron, but when travelers would come he would find out what gods they worship and he use the illusion to make the shrine appear to be the appropriate deity. You think you are praying to Helm but the jokes on you, it's really Levistus!

Quote from HailRobonia >>

Once you can cast 6th level spells you are required to go crazy with illusions. My illusionist warlock created a whole town that was mostly illusions.  The buildings were cheaply made just to keep wind/weather out and then covered with illusions of houses, a tavern, etc. Most important was the temple. It was a a shrine to his fiendish patron, but when travelers would come he would find out what gods they worship and he use the illusion to make the shrine appear to be the appropriate deity. You think you are praying to Helm but the jokes on you, it's really Levistus!

 That sounds perfect.

Quote from HailRobonia >>

Once you can cast 6th level spells you are required to go crazy with illusions. My illusionist warlock created a whole town that was mostly illusions.  The buildings were cheaply made just to keep wind/weather out and then covered with illusions of houses, a tavern, etc. Most important was the temple. It was a a shrine to his fiendish patron, but when travelers would come he would find out what gods they worship and he use the illusion to make the shrine appear to be the appropriate deity. You think you are praying to Helm but the jokes on you, it's really Levistus!

 You thought you were praying to Pelor, but it was I Dio

Awesome spell! You can go to Mirt's mansion and make it look nice, and when Mirt wakes up he freaks out. Then with disguise self you make yourself look like Mirt's deity and tell them to give your player's the Lord's Ensemble.

Quote from HailRobonia >>

Once you can cast 6th level spells you are required to go crazy with illusions. My illusionist warlock created a whole town that was mostly illusions.  The buildings were cheaply made just to keep wind/weather out and then covered with illusions of houses, a tavern, etc. Most important was the temple. It was a a shrine to his fiendish patron, but when travelers would come he would find out what gods they worship and he use the illusion to make the shrine appear to be the appropriate deity. You think you are praying to Helm but the jokes on you, it's really Levistus!

 Yes.

This is a great spell to give your bad guy.  I recently Had my bad guy use it to make a hallway look like it was full of whirling blade traps. So the party saw the whirling blade traps and the lever on the far side. They immediately figured pull the lever disarm the trap and didn’t look for anything else. So what they missed was the pressure platter halfway across and the lever both opened vents in the ceiling that dropped level appropriate oozes down on the area with the illusion blade traps.  

So if you cast this at 6th level, could you have a permanent illusory follower? All you have to do is use your actions while traveling to have them follow you (I guess they’ll just stand in the background during combat). I don’t know what benefit it would have, but it’s neat. Maybe your bard has an illusory fan, or your wizard is followed by an illusion of their old mentor.

By the time you have 6th level spells, you could cast programmed illusion instead. Useful if you have limited spells known and want the illusions earlier.

Would I be able to use this to have Elton John sing 'I'm Still Standing' with accompanying music?

So I have a question about the spell Major Image, if I create a Illusion of a creature that is already transparent and non-tangible (like a ghost or a air elemental) would a person trying to perform a Physical interaction would it revile that it is an illusion?

@breemaker the spell says "Physical interaction with the image reveals it to be an illusion" so Yes, the creature physically interacting would realize it is an illusion. However, another creature observing the first, interacting with the illusion is less likely to suspect shenanigans, so less likely to make an Intelligence (Investigation) check.

Be a level 14 illusionist wizard. Cast this spell at sixth level to make a 20foot ship. Use illusionary reality to make it solid. You know have a permanent airship as long as you refresh your illusionary reality once per minute whilst flying. 

May I ask how? Were you a Wizard/Warlock multiclass? Cause Warlocks only get access to 5th level so they can't make permeant illusions.

By illusionist warlock I meant "warlock with a lot of illusions spells/abilities" not an actual multiclass.

I mean still, as a warlock you can only cast this spell at 5th level so nothing you make can be permanent

Subtle spell + major image = chef’s kiss 

Quote from ApolloOnMars >>

So if you cast this at 6th level, could you have a permanent illusory follower? All you have to do is use your actions while traveling to have them follow you (I guess they’ll just stand in the background during combat). I don’t know what benefit it would have, but it’s neat. Maybe your bard has an illusory fan, or your wizard is followed by an illusion of their old mentor.

Honestly if a player asked to do this while I was DM, I would just give them an illusory familiar without requiring them to cast and recast this spell a bunch.

If your in a situation where you have to track a group though icy mountains use major image to make the group feel warm and watch as they slowly die from frostbite. 

The temple thing is a clever prank, but that's not how worship works. Someone praying to Helm at a disguised Levistus shrine is still praying to Helm and not Levistus. Their faith and allegiance would be unchanged. At most a god might be slightly annoyed that their follower was deceived but Levistus wouldn't be gaining anything in particular from the deception. It's not like the travelers would become Levistus converts because they unknowingly prayed at the wrong shrine.