Four, $A, B, C=$ Three countries are holding a Go broadcast tournament, each team with 9 members. The rules are as follows: Each match involves one person from each of two teams competing, the winner stays to defend, the loser is eliminated, and the other team sends one person to challenge. The first match starts with one person from each of $A$ and $B$ teams, and then proceeds in sequence. If any team's 9 members are all eliminated, the remaining two teams continue to compete until another team is completely eliminated. The team of the winner of the last match is the champion team. Answer the following questions and provide reasons:
(1) What is the minimum number of wins for the champion team?
(2) If the champion team wins 11 matches at the end of the tournament, what is the minimum number of matches that could have been played in the entire tournament?
Solution: (1) When the champion team finally wins, the other two teams' 18 people have all been eliminated. Since team $C$ plays later, when $C$ team wins the championship, it can win one less game. To minimize the number of wins for team $C$, teams $A$ and $B$ need to eliminate as many of their own members as possible through mutual matches.

According to the match procedure, for every two adjacent members of teams $A$ and $B$ who are eliminated, there must be one member of team $C$ who is also eliminated. Since team $C$ can have at most 8 members eliminated, the number of members eliminated from teams $A$ and $B$ through mutual matches is at most 9. Therefore, team $C$ must win at least 9 games.

On the other hand, if $A_{1}$ consecutively defeats $B_{1}, C_{1}, B_{2}, C_{2}$, ..., $B_{8}, C_{8}, B_{9}$, and then $C_{9}$ defeats all 9 members of team $A$, team $C$ will win the championship with exactly 9 wins.
In summary, the champion team must win at least 9 games.

(2) If the champion team wins a total of 11 games, 11 of the 18 people from teams $A$ and $B$ lose to members of the champion team, while the remaining 7 are eliminated through mutual matches between teams $A$ and $B$. Therefore, 6 members of team $C$ are eliminated. At least 24 games are played in total.
On the other hand, if $A_{1}$ consecutively defeats $B_{1}, C_{1}, B_{2}, C_{2}$, ..., $B_{6}, C_{6}, B_{7}$, and then $C_{7}$ consecutively defeats $A_{1}, B_{8}, A_{2}, B_{9}$, $A_{3}$, ..., $A_{9}$, team $C$ will win a total of 11 games and win the championship, with a total of 24 games played.
In summary, the entire competition must have at least 24 games.