So, my husband and I have a tradition of getting each other a cool/unique/nerdy new mug for Christmas each year. I didn't think I'd be able to top the beaker mug (I'm a Biochemist) my husband got me last year but I think with this I'll take the lead again! He's a huge Pac-Man fan (yes, as 30-somethings we're constantly trying to re-live the 80's and early 90's). Pac-Man and Mrs. Pac-Man were always his favorite games. I can't wait for him to open this on Christmas!I personally couldn't wait till Christmas to test it out, so I opened the box while he was at work and heated up a mug of water in the microwave to see it in action!First, the mug seems really high quality/well made and is a standard size mug. Doesn't seem cheap like some I've bought. Second, you should know that simply filling it up with warm tap water isn't going to bring the scene to life. The liquid inside the mug and the mug itself have to be HOT for Pac-Man to show up. It took about 45 seconds in the microwave before I started to see it appear. Once it does appear fully (the outer edges took a little longer than the stuff in the middle - see my pic of it still sitting in the microwave after I stopped it) it looked great!! I love that it's in full color and I love that what appears is different on each side of the mug.Also, I dumped the water out and dried it immediately after taking the pictures and dried it so see how long it would take for the heat activated parts to disappear again. It took a full 10 minutes or more of the mug sitting empty on my table before it looked the way it did straight out of the box. I think that's great actually. Means the heat activated parts can be enjoyed the whole time you drink your beverage of choice, even at sipping pace.Once the pictures had faded completely the mug looked exactly the way it did when I took it out of the box. I haven't washed it yet to comment on how it holds up to washing, but will update after Christmas and its first real test run. As of now though, I am thrilled with this mug and can't wait to give it to the hubster. I know he'll love it!I did NOT receive this item for free or at a discount.I received the pacman heat change mug. The seller did a good job of sending it quickly but the product itself leaves a bit to be desired...First, the mug says 'not microwave safe' at bottom. That kind of defeats the purpose for those with on-the-go lifestyles. I would like to think that I could just place the mug in the microwave for a hot cup of tea, chai, etc. I don't believe it's dishwasher safe as well according to the label (please check your packaging...).Last but not least, please do NOT purchase this mug and expect it to have flashing, neon features like the game. It's true there's color once the mug is heated but it's nothing close to the neon brightness of the game. It's more like shiny yellow, blue, red paint appears.Basically, I give this mug 3 out of 5 stars. I'm a kid of the '80s so it's a be of nostalgia for me buying this mug. Reminds me of the days of being a carefree teen in the arcade at the local mall. Just a walk down memory lane briefly - that's good enough. Don't expect the paint to last. I have never placed this mug in a microwave but after using it a few months, I have noticed the paint takes quite some time to activate even after being exposed to hot water for tea or coffee.This is a very nice mug. I've been a fan of Pac-Man my whole life, so this was a must-have. The heat change however is both an example of a neat idea & lousy execution. When you put steaming hot coffee in it the black film over the artwork becomes transparent, which in my opinion tells you the coffee is too hot to drink, and once it's at a drinkable temperature (but still hot) the film becomes black again. The problems with this are thatA: The film never becomes completely transparent, giving the artwork a foggy look.B: When the drink is cool enough to consume, the pac-man maze is empty.C: The thermal stickers over the artwork come off very easily, even when carefully hand-washed.The odd twist about problem C though is that as the stickers begin to fall off, the artwork shines out clearly & beautifully, so it's hard to say it's a negative. Overall though I would definitely recommend it unless the heat change feature is your sole reason for buying it, but my guess is it'd be secondary to the fact that it's Pac-Man.cute cup works when heat applied but kinda of smaller than i expectedWorks as promised! I read multiple reviews saying it was a knockoff and that by washing it the heat stickers come off. I have not had this problem, I do not have a dish washer so I wash it gently by hand and the decals have not come off at all. Also the picture of the game is like a real game, so some of the gold coins have already been "eaten" and are missing, the characters are not spread out perfectly- the picture is more like a screen shot of an actual game so not everything is spread out.I had gotten an identical mug from five below that broke and replaced it with this expensive pac man mug because I couldn’t find it anywhere at a reasonable price anymore. I am so disappointed in the fact that the pacman decorations kept flaking and chipping off, even with me being careful not to scrub at those areas. Never been in the dishwasher. Not worth the money at all.Lights up nice when the cup is filled with hot water.I was a little disappointed when I saw that the ghosts and Pac-Man all had a weird shadow around their borders that becomes evident when the cup is hot. If you have actually ever played Pac-Man, and you're not just some pseudo-nerd poser buying the cup for gamer cred, you'll notice a discrepancy on one side of the cup because there is an extra ghost and one of them is illuminated and vulnerable while the others are in their normal attack state. It's cute, I guess overall, but it could be better-looking and more accurately reflect actual gameplay.Got it for my mums birthday because she asked for a mug and thought it was petty funny, showed how it works and she liked it, although a few days after she'd taken it work, even though she read the instructions and i told her to not put it in the washing machine, she put in the washing machine which had messed up the heat thing and now its just a normal mug. Good product but its probably going to be ruined pretty soon.I bought this for my boyfriend as part of a christmas present as he loves things like this. It's not a bad buy, but it fades a little after a few washes, but then again, so do most mugs after you wash them! He liked it anyway, and the price wasn't bad for a little novelty gift :)It looked fantastic for the first week or so however when I washed it, the outer coating started to peel away. I only washed it in warm soapy water so I was surprised it was not more durable. On the plus side, the mug design is very good.Bought as a XMAS gift for a friend. Transfers containing heat change wiped off on first use (very poorly applied, we didn't even wash it yet). Handle has cracked off now as well after 1 wash. This is extremely bad quality and at £5.95 is expensive for a 1 or 2 use item. I strongly suggest avoiding this entirely.Have bought this as a stocking filler so hope it will bring a smile to someone's face. Don't know how durable the heat change will be but it looks good and is nicely boxed, so seems like good value for money.