Defending champions Germany shouldn't fear anyone. Qualifying was a cakewalk with 10 straight wins and after lifting the Confederations Cup, they won't be fazed by what lies ahead.
Two of their games last summer were in Kazan and Sochi, where the Germans face Sweden and South Korea in 2018. Adaptation won't be as big a problem for them as it is for South Korea and the Swedes.
Mexico also know what to expect following their participation in the Confederations Cup, too. What will they have learned from that 4-1 defeat to Germany in the semifinals?
1. Germany -- Anything other than top spot would be a huge surprise. The Mexicans are Germany's highest-ranked opponents and the World Cup holders' B-team battered them in the summer.
2. Sweden -- The potential of Zlatan Ibrahimovic coming out of retirement changes things, although this Sweden side is very well organised and Germany know very well the threat posed by Emil Forsberg.
3. Mexico -- When it comes to the crunch, as it did in the Copa America Centenario and the Confederation Cup semifinal, Juan Carlos Osorio doesn't seem to have an answer. He'll face not only Germany, but also Sweden -- who the Mexicans have never beaten.
4. South Korea -- Even with Son Heung-Min, the South Koreans lack cutting edge up front and ultimately that could cost them here.
Must-see match: Germany vs. Sweden
Easy. It has to be the game in Sochi on June 23 between Germany and Sweden. For whatever reason, fireworks happen when these two meet. There was a 4-4 in 2012 when Sweden came back from 4-0 down. Germany coach Joachim Low will no doubt point to that qualifier to guard against complacency. Then there was the 5-3 a year later. On that occasion, the Swedes went 2-0 up and gave Germany quite a scare until Andre Schurrle, who set up Mario Gotze's winner in the 2014 World Cup final, decided enough was enough and scored a hat trick.
X factor: Germany
Last summer's win in the Confederations Cup should, in theory, serve as perfect preparation for Low to make Die Mannschaft the first team to retain the World Cup since Brazil in 1962.
Germany triumphed in the warm-up tournament with a second-string side while their Under-21 team were busy winning the Euros. The problem -- and we're splitting hairs here -- is the curse of the Confederations Cup.
No winner has ever followed it up with World Cup glory the following year. Can Germany lift the hex?