I know it's tough, handing over your precious to just anyone to alter and possibly ruin it. I've been there and it's heart breaking. Artists who have the right idea but just don't understand preservation of the card. There is no need to worry about that here, thankfully.
Aside from being a Bachelor's graduate in fine art and illustration with a minor in acrylics, and getting out of Dodge in the top percentile of my class, twice, I live and breath this life. I'm not only a painter/illustrator for a living, I am also an avid collector, and a store owner. Magic is the life blood of Excelsior and I take my role VERY seriously.
All of my materials are 100% archival, meaning there is no excess acid (or base). This is important because eventually they will eat their way through the paper and completely devalue any card. Everything I use also has the lowest moisture content and I paint dry. Though the faces of the cards are sealed, excess water finding it's way between the layers, splitting your card, and killing its value in the process. You end up with this spongy, mushy pile of yuck..... that just wont do.
After your card has been painted, I sleeve it. First, in a pro-fit sleeve, (clear, close fit sleeve made by ultra-pro to slide into another properly sized sleeve) I place the pro-fit upside down to help seal out excess dirt and moisture. These sleeves are $2.99 for 100 and I highly recommend sleeving your entire deck this way. Keeps people from thinking you have marked your deck, plus, they are REALLY thin and give your cards just a hair more protection. Altered cards should always be sleeved!!! Both to protect the card and its new artwork, but also because no matter how hard i try, paint can show through the sides of the card. and cheating, even by accident, is lame
All alters can be done in such a way that makes them legal for tournament play. If you are unsure, ask your local judge. Rulings on alters do vary from judge to judge but generally follow the same guidelines.
While altering the image is the most obvious change, physical modifications should also be taken into consideration.
Weight and flexibility are far from being concerning. A thorough analysis of each card with a bunch of manipulation would be required to be able to detect the marked card among regular ones. This would be so easy for a judge to catch that it's highly unlikely to happen without being very noticeable. Thickness and shape, on the contrary, may be more concerning.
- Sharpies won't add thickness.
- Ballpoint pens may leave furrows that are visible and/or detectable on the back of the card. These aren't widely used for alterations, though
- Painting is the most widespread technique to alter and depending on the material used results may vary: while acrylics are fine enough, oil painting and gouache may be too thick.
We therefore enter the realm of detecting marked cards. Put the deck in one pile and look for a space between two cards. The trick here is that this extra thickness may only exist on one of the four sides of the card. While foils can be unbent, thickness can't be removed, possibly leading to the player not being allowed to use the card.
Similar to thickness is the card's texture. If you pass a finger against the front of a card, you may be able to recognize an altered card. Just like weight and flexibility, this requires obvious manipulation and doesn't deserve more attention than that to catching a regular manipulator.
If the original condition of an altered cards wasn't perfect, the painting may have kept the card in a marked condition (bent, for instance). This requires a fix that's the same as for foils.
To sum it up, it's not because a card is altered that it's marked (just like the foilness of a card doesn't imply a marking). Just apply the usual detection-of-marked-cards process and it will be fine.
It's far from easy to define clear rules about what's allowed and what's not. If detecting marked altered cards isn't especially hard, as the process is classic, drawing clear lines for allowance of the "new" image is close to impossible. That's why the rules give complete power to the head judge to determine the suitability of a card.
The impact of the alteration on understanding the game state is the most important thing to keep in mind, much above the manipulation problems that may arise. Do not forget that all of your players may not know the format as well as you. In addition, a player in his game is not as relaxed as you are when you evaluate something before the tournament starts. Still, don't become paranoid! While the balance is pretty hard to find, it proves to be an interesting exercise that may also help you understanding what's really dangerous with foils, i.e. the player's behavior more than the cards themselves.
Of course, you could just ban all altered cards from your tournaments to limit the risks. But keep in mind that Magic is a game that has created a community around it. Most players just want to play with cards they like and have fun while playing. Altered cards are currently one of the ways to achieve this goal, just like foils and Japanese cards have been.
Magic: The Gathering, Mana Symbols, Images, and Intellectual property pertaining to Magic, is copyrighted and belongs to Wizards of the Coast Inc., a subsidiary of Hasbro Inc. what I offer is a service that paints and alters existing cards for the enjoyment of players and collectors. I do not wish to imply that anyone other than the original artists should be credited to the art printed on the cards prior to them being altered.
If you have any questions, call the store, or shoot me an email from the "How to order" tab