At 10th fighter level you can spend 4 rest dice to call up to 2 allies within 60ft to arms. Doing so costs a bonus action or move action and cannot be done more than once per turn. The chosen allies then can then immediately perform an action.
At 10th fighter level, choose two upgrades from the list below:
Siegemaster - Gain a +1 bonus to crossbow and thrown weapon attack and damage rolls. When using To arms! you can also include an ally, whos only allowed action is to make a crossbow, bow, thrown/launched weapon, or ranged spell attack. Gain a +2 bonus to checks made to participate in, repair, and oversee siege and demolition engine and equipment creation.
Route marcher - You and your allies can move through difficult terrain unimpeded when traveling, and do not incur traveling, rest, or overworld penalties from terrain. All fatigue damage taken from travel to the party is reduced by 1. You ignore one instance of bulk from armor and equipment, and your movement speed is increased by 5ft.
War master - During a rest you can spend 3 rest dice to grant all allies an inspiration dice. A character cannot have more than one inspiration dice. Gain a +2 bonus to intimidation and persuasion checks.
Redmane - You gain benefits while wielding lighter armors than heavy:
No armor: Gain a +3 bonus to AC and a +3 bonus to weapon attacks.
Light armor: Gain a +2 bonus to AC and a +1 bonus to weapon attacks.
Medium armor: Gain a +1 bonus to AC, gain an extra instance of block at the start of combat, gain a +1 bonus to melee weapon attacks.
Ledger of war - You gain a +2 bonus to checks made to manage, procure, secure, and exchange you and your allies supplies and property. When you or an ally attempts to create a consumable or tool during a rest, you may spend 1 rest dice to double the amount created. When an ally is modifying, altering, or creating a non-consumable item or object, you may spend 1 rest dice to grant them a +1 bonus to associated checks.
Runic shield - You may attune to your shield and properly mark it with a rune of your own during a rest. If you do so, it provides an extra instance of block to you at the start of combat, and all beneficial spells have their range doubled only for the purpose of targeting you.
Weapon of conquest - Choose a specific weapon type from a weapon group. You can attune to one during rest, increasing its damage dice by 1 size category.
Raid leader - Increase the number of allies affected by Call to arms! to 3.
High lord - Gain a +10 bonus to max HP, and gain an extra ring slot, gain a +1 bonus to wisdom saves.
Veteran - You and allies in your party gain a +1 bonus to stealth, survival, and deception checks. You gain a +3 bonus to investigation and insight checks during rest. Increase max rest dice by 1.
Gain an extra upgrade at 12th level.
At 11th fighter level, gain a +1 bonus to social checks and a +1 bonus to charisma and intelligence checks.
Progress proficiency with cartographers tools: proficient > expert > you can read and compile maps of enchanted areas, melded spaces, and structures in realms like the ethereal plane, and gain a +2 bonus to checks made to read such documents.
Progress proficiency with navigators tools: proficient > expert > You gain a +3 bonus to checks made to detect hidden passages, enchanted paths, or secret spaces.
Progress proficiency with scribes tools: proficiency > expertise > Learn 2 languages and gain the ability to learn a lvl 1 arcane spell that you can cast by spending 1 rest dice.
At 12th fighter level, you can use a single-ally version of To arms! by spending only 1 rest dice, allowing you to grant a single ally an action immediately, but not allowing you to grant other allies actions from commanging traits upgrades.
At 12th fighter level, you gain a +5 bonus to initiative checks. While first in initiative order, you gain a +1 bonus to all d20 rolls.