Phase 1/World 2/2-3


 * Conclusion for chance to go to boss node:
 * 37.5% chance if fleet doesn't contain CV(L) or AV
 * 42.5% chance if fleet contains CV(L)
 * 59.5% chance if fleet contains AV

Tips
After leveling submarines to about level 10 and modernizing them to 4-5 stars, you can use them to grind 2-3 for some Daily and Weekly quests while picking up resources. (A tactic most admirals call "Orel Cruising".)

1. A fleet which contains at least 3 submarines is recommended. The more submarines you use, the easier the map will be.

2. Submarines with high luck should be placed at the bottom of the fleet list to increase their chance of performing cut-in attacks on the stronger enemies during night battles. Doing this can help you achieve an A or S rank victory, especially if you have to fight the enemy fleet located at node G.

3. Submarines should be fully modernized (at least fully upgraded torpedo attack and armor) and non-remodeled because non-remodeled submarines have shorter repair time and consume very few resources when resupply (especially ammo). Please note that compared to a non-remodeled submarine, '''a remodeled sub will take twice the amount of time to repair. [ SSV requires twice amount of time to repair than SS* ]'''

* This does not include, or  as they do not remodel into SSVs. However, their increased health means a longer repair time should they take more damage.

4. This method does not guarantee victory every time, especially if you hit the boss node and have an unlucky run.

Trivia
Quests B14 OR B19 AND B17 can be done at the same time. 1 boss for 2 quests. You can mix B20 with B17, however it is not recommended due to the lack of firepower.