As far as I have understood it, weapons r and higher have a skill. The maximum level of said skill is 20 and they work as multipliers for the respective decks?

now there are 3 rarities of weapons with skill. and several different skills (like assault and defender)

Question one:

Simple upgrade formula for 100% chance skill increase is what?

Current skill lvl = amount of weapons of one tier lower needed to increase skill lvl by 1.
Example: SR Weapon skill lvl 4 , so 4 R weapons needed to increaese skill lvl to 5 with a 100% chance?


Question 2: Should one focus on maxing out one skill first or spread the skill levels equally around the deck?

Quesiton 3: should one keep duplicate SR weapons (assuming you have already broken the limit to the maximum) as fodder for SSR weapons or simply use it on other SR weapons?