It is unfortunately unknown how to replicate this. It's effect makes your level jump from what level you are currently at to a higher level. An example being Level 1 → Level 54.
It is unknown if it is fixed, but if you continuously minimize and maximize the browser, sometimes the chests will show up twice (about 1/2 a second apart) and you can get the rewards of both chests. This also works with spells (double spells). You could take advantage of this to get parts for a quest twice as fast but it is hard to execute and sometimes doesn't work.
Double Daily Reset Rewards
There is many parts to this exploit but in reality it is very simple. Reset rewards include; bounties, daily reward bonuses, wheel spins, and some other ones to be found. Players can receive double the normal amount of these rewards by changing the time and/or date while the game is open.
For example, If I had gone to the Town Square in Lamplight Town and had just spun the Left Wheel and/or the Twilight Wheel I could spin the wheel again (but with different items on the spinner) even without membership.
All you have to do is spin the wheel for today, change the date on your computer for sometime far in the future (so you don't accidentally decline the next days reward) and refresh the page, then when you log back in there will be another chance to spin and you still get the current-day reward. It is the same deal with members except you get 4 rewards instead of 2.
You can do this with daily rewards (the rewards you get at the beginning of the game that get better as you hold a streak), wheels in town square, and bounties.
Note: If you go out of the specific place you are in like town square, and you walk out to another place in the same map, your date will be automatically synced back to the current date.
(Simplified) By changing the date of your computer, phone, etc, farther in the future, and refresh your page, you can get double daily rewards.
You could take advantage of this to get more gold or possibly items, but in total it does take up a lot of time. This is something you can try that works with Google Chrome, and is easy but can be not worth the time.
Infinite Daily Reset Rewards
The glitch above actually works infinitely on the iPad app. Just get the prizes, set the date 1 day forwards, get the prizes again, set one day back, and repeat. This can let you do 10+ spins in a day.
Infinite Wheel Prizes
Changing the date on a Computer to the next day can make you get infinite prizes, just keep changing the date forward and back.
If you are wearing member clothing when your membership expires, it will stay on you unless you take it off and try to put it back on.
Rarely, Fire can do more damage to Water monsters. This is a uncommon glitch.
Misplaced character bugPlayers can walk on blocked places such as walls while you can't. So they can go out of bounds (out of the map), and others. This may happen because the wizards in one room are appearing in the one you are currently in.
Double Map Bug
Sometimes if logging on to your account on 2 different tabs you will find decorations from the first map overlaying the current map (however this is purely graphical).
If your computer/mobile device goes into sleep mode during an arena battle when you reopen your computer you will be stuck in it and lose 50 trophies.
Question Correct Bug?
(Simplified explanation) "You get 5 dollars a hour, if d is total dollars and h is hours then what is the equation?" (d = 5 * h) This question seems simple but you cannot say d = h * 5 even though d = h * 5 (Incorrect) is equal to d = 5 * h (Correct). It is unsure if this affects any other questions.
Question Picture Bug
Instead of a picture, the code for it will show up.(I can’t get the pic to show up right)
Player Card Bug
If you walk towards the Twilight Wheel in Lamplight Town before it's time to spin the wheel and pull up a Player Card before you get there, the Member Card will fuse with the Player Card.
World Map Bug
When logging into Prodigy and clicking "All Worlds", all the servers will appear full even though they aren't. I'm not sure what causes this to happen.
Sometimes, buddies will show up, but not the wizard.
Battle Background Bug
If the internet goes out in the middle of a battle and you choose to attack, the question refuses to show and instead you get just the background.
Glitched Bounty Bug
Randomly, when you get a bounty you will find the bounty monster is not there, and it will never be there and you will always have one pending bounty to turn in. Rest in peace people trying to get blackfang like me.