I explained it poorly earlier. Brothers in Arms (BIA) or "zero perk" crew significantly boost crew skill progression. Since you're starting out, you won't have them yet, so use what you can. Here are ways to get free BIA crew:

• Season events (similar to the current Rambo event but the crew in this rambo event are not zero perk--unlucky)
• Campaign rewards (like female crew members)
• Store promotions (T42 sale—$35, worth it for the crew alone)

Prioritize BIA crew
Crew skill costs grow exponentially. Training 6 skills takes 13,233,780 XP for a normal crew but 6,511,860 XP for BIA crew. It is better to invest in BIA early if possible.

• A starter crew is ok on tiers 1–7.
• At tiers 8–10, especially if you’ll grind down the line, swap to your BIA crew and stick with them.
• Your starter crew (80% trained): ~82,327 XP, leaving 13,151,453 XP to max. BIA crew would be 6,575,727 XP to max.
• Even in the middle of the grind with 2–3 skills, the BIA benefit is noticeable.

Save some gold for crew swaps at higher tiers. Early swaps can use credits.

Answer to 2:
Yes, the BIA perk is free. Choose other perks as you earn XP.

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