Izzet League:

Food & Cuisine:
?The Izzet generally don't care about food. So long as there's something on their plate, and it's edible, and doesn't taste awful, they'll eat it anyway. This was mostly started by the goblins, but then spread to the other members of Izzet society, since they saw that by not worrying about food, they can spend more times in their labs or on the testing field. The only time an Izzet becomes interested in food is if they can come up with some Rube Goldberg monstrosity that butters toast or something, involving generators, thaumic particle accelerators, and small-to-large explosives.

?As far as vices go, drugs are not in favor in the guild, and uppers, while also illegal are more acceptable, because that increases productivity. Hallucinogens are prized and not illegal, because sometimes they lead to breakthroughs (and sometimes to pulling levers that aren't there, or pulling the wrong lever and explosions). Nootropics are a big thing however. The rule of thumb is, if it makes the person smarter or more creative, the members of the League will use it, legal or illegal.

Leisure and Recreation:
?The Izzet are workaholics and the stereotype with them is that they don't have fun. Nothing can be further from the truth. The Izzet League is the foremost owner and builder of various amusements parks. Roller coaster rides, pirate ships, gyro towers - you name it, they designed it, built it, re-invented it, and re-built it after the explosions gone off too early. Naturally, all Izzet get in free, and often come up with new plans while experiencing a death-defying drop.
?
?Races, regattas, and air races are a popular pastime as well. Labs will compete with each other who can make the fanciest and fastest vehicle. If it gets to the finish line in one piece with the pilot still intact, that's bonus points. Other than this, the Izzet read a lot, so libraries are as big of a deal as with the Azorius and Simic, although in the case of the Izzet, all of their books are made from non-combustible materials, just to be safe. Izzet generally have a preference for fiction, since those give them ideas.

Friendship & Conflict:
?Izzet friendships are defined by conflict. The best friends are lab rivals - competing project ideas, competing for funding, competing on who's more correct about the proper application of theory, and so on. Generally speaking it starts as a rivalry but blossoms into friendship once the projects are done, funding is secured, and theories have been applied. ((If only this worked in the real world.)) Generally speaking, Izzet League scientists see themselves as carriers of ideas and it's the ideas that are competing, not the actual scientists.

?Actual enmity and conflict are rare, but they do happen. Generally, there are two ways in dealing with it. The more rational League members will bring in the Azorius Senate as arbitrators and both will accept their ruling. The more passionate will unleash their creations against one another, until one (and sometimes both labs) are reduced to a smoking crater. The option to petition Niv-Mizzet is open, however, in the overwhelming majority of cases, this leads to the "two smoking craters" options.

Relationships and Sexuality:
?The Izzet are experimenters, so the guild has no proscriptions regarding gender roles or sexuality. Do whatever and whoever you want. Some rivalries turn into sex and some experimental data has been ruined when the lab table was used as a platform for passion (and happily, the experiment had to be repeated anyway). No real taboos exist, since the guild is made to push boundaries.

Childhood & Old Age:
?Izzet children have access to the best technical schools in Ravnica. Izzet schools generally try to foster both a rational methodic approach and passionate inspiration. This is also the phase when Izzet children will most likely be gently pushed out of the guild, if the child's temperament or intellect doesn't match the guild. Those that aren't generally are allowed to join whatever experiment strikes their fancy. On completion of schools, they'll go be lab assistants to better scientists until they can run their own projects and so on.

?Izzet League elders are very respected. Since League standing is by merit, these people usually have the most papers and projects. Most don't really retire, since they're so consumed by their passion projects that they'll keep going until they give out. Sometimes however, the collected experience the elderly person has is good enough to get them to become an advisor to Niv-Mizzet. These people have a quasi-divine aura to them, second only to Niv-Mizzet himself.

General Notes:
?The Izzet League is full of passionate scientists. They're constantly torn between their rationalism and romanticism, with "In the Name of Science!" to be a rallying call.