Expansion Skill List from GBO2 Wiki

Here's an initial list that people have gathered from the Japanese wiki (https://w.atwiki.jp/battle-operation2/pages/1354.html#id\_63720f6b)

Melee / Ranged Strength Expansion

  • Lv1 = X Strength +2, Max X Strength +2
  • Lv2 = X Strength +3, Max X Strength +3
  • Lv3 = X Strength +4, Max X Strength +4
  • Lv4 = X Strength +6, Max X Strength +6
  • Lv5 = X Strength +8, Max X Strength +8

Ballistic / Beam / Melee Resistance Expansion

  • Lv1 = X Resistance +2, Max X Resistance +2
  • Lv2 = X Resistance +3, Max X Resistance +3
  • Lv3 = X Resistance +4, Max X Resistance +4
  • Lv4 = X Resistance +6, Max X Resistance +6
  • Lv5 = X Resistance +10, Max X Resistance +10

Thruster Expansion

  • Lv1 = Thruster +2, Max Thruster Limit +4
  • Lv2 = Thruster +3, Max Thruster Limit +6
  • Lv3 = Thruster +4, Max Thruster Limit +8
  • Lv4 = Thruster +6, Max Thruster Limit +12
  • Lv5 = Thruster +10, Max Thruster Limit +20

Custom Part Expansion [HP]

  • Lv1 = Unit HP increases by 50 for each "Attack" type custom part equipped.
  • Lv2 = Unit HP increases by 100 for each "Attack" type custom part equipped.
  • Lv3 = Unit HP increases by 200 for each "Attack" type custom part equipped.
  • Lv4 = Unit HP increases by 300 for each "Attack" type custom part equipped.
  • Lv5 = Unit HP increases by 400 for each "Attack" type custom part equipped.

Custom Part Expansion [Attack]

  • Lv1 = Melee Strength increases by +1, Ranged Strength increases by +1 for each "Movement" type custom part equipped.
  • Lv2 = Melee Strength increases by +2, Ranged Strength increases by +1 for each "Movement" type custom part equipped.
  • Lv3 = Melee Strength increases by +2, Ranged Strength increases by +2 for each "Movement" type custom part equipped.
  • Lv4 = Melee Strength increases by +3, Ranged Strength increases by +2 for each "Movement" type custom part equipped.
  • Lv5 = Melee Strength increases by +3, Ranged Strength increases by +3 for each "Movement" type custom part equipped.

Custom Part Expansion [Armor]

  • Lv1 = For each "Auxiliary" custom part equipped: Ballistic Resistance +1 Beam Resistance +1, Melee Resistance +1
  • Lv2 = For each "Auxiliary" custom part equipped: Ballistic Resistance +2 Beam Resistance +1, Melee Resistance +1
  • Lv3 = For each "Auxiliary" custom part equipped: Ballistic Resistance +2 Beam Resistance +1, Melee Resistance +2
  • Lv4 = For each "Auxiliary" custom part equipped: Ballistic Resistance +2 Beam Resistance +2, Melee Resistance +2
  • Lv5 = For each "Auxiliary" custom part equipped: Ballistic Resistance +3 Beam Resistance +3, Melee Resistance +3

Custom Part Expansion [Thruster]

  • Lv1 = For each "Special" custom part equipped: Thruster +1
  • Lv2 = For each "Special" custom part equipped: Thruster +2
  • Lv3 = For each "Special" custom part equipped: Thruster +3
  • Lv4 = For each "Special" custom part equipped: Thruster +4
  • Lv5 = For each "Special" custom part equipped: Thruster +5