what's not to understand
there 3 skill trees each with 5 skills
You get SP from battles which helps you learn your current skill
You can hit the minus button and link your skills to other party members. The higher affinity you have with that party member, the more skills you can share with them. This is where those affinity coins you've been collecting from level ups and unique monsters come into play because it costs a certain amount of coins to share a skill
Like after getting the heavy armor skill with Reyn, I shared with Shulk so he can wear Heavy armor too
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