Free-to-play tacticians, here's how I passed Squad Assault 5 to acquire the Squad Ace E 1 Seal. This one is notably easier than the ones before it, so you could probably improvise and still pass it.
You'll probably want to equip all the required Skills and Seals before you begin. Remember to write down which units you are going to use, along with any special requirements for each one.
1 - Zephiel 4*: Red Sword Tank
2 - Arvis 4*: Ranged Damage
3 - Clarine 4*: Healer (Wrys)
4 - Sully 4*: Blue Lance
Essential:
1 - Red Tank
3 - Healer for Tank
Chapter 1-2: Lovely Bloom
Team:
1 - Selena *4: Red Sword
2 - Felicia *4: Magic Tank
3 - PA! Olivia *5: Dancer
4 - Cecilia *4: Green Mage
Essential:
2 - Magic Staff Tank
Chapter 1-3: Two Noblewomen
Team:
1 - Raigh *4: Rauorwolf Mage (Anti-Cavalry)
2 - Narcian *4: Green Axe Tank (Arthur)
3 - Robin F *4: Gronnwolf Mage (Anti-Cavalry)
4 - Palla *4: Red Sword
Essential:
Anything capable of killing four Cavalry Units.
Chapter 1-4: Blade and Dancer
Team:
1 - Lilina *4: Red Mage (Sophia)
2 - Clive *5: Blue Lance Tank (Subaki)
3 - Olivia *4: Dancer
4 - Corrin F *4: Blue Mage Tank
Essential:
2 - Blue Tank
Chapter 1-5: Captive Princess
Team:
1 - Black Knight *5: Distant Counter Tank [Seal - Distant Def 1]
2 - Clarisse *4: Archer
3 - Ursula *4: Blue Mage
4 - Lissa *4: Healer [Seal - Spur Def 1]
Essential:
1 - Distant Counter Tank
4 - Healer for Tank
*If you're having trouble, watch Baka Jam's strategy from YouTube
You'll probably want to equip all the required Skills and Seals before you begin. Remember to write down which units you are going to use, along with any special requirements for each one.
*** Obligatory Possible Spoiler Warning ***
Chapter 1-1: Willful Warrior
Team:1 - Zephiel 4*: Red Sword Tank
2 - Arvis 4*: Ranged Damage
3 - Clarine 4*: Healer (Wrys)
4 - Sully 4*: Blue Lance
Essential:
1 - Red Tank
3 - Healer for Tank
Chapter 1-2: Lovely Bloom
Team:
1 - Selena *4: Red Sword
2 - Felicia *4: Magic Tank
3 - PA! Olivia *5: Dancer
4 - Cecilia *4: Green Mage
Essential:
2 - Magic Staff Tank
Chapter 1-3: Two Noblewomen
Team:
1 - Raigh *4: Rauorwolf Mage (Anti-Cavalry)
2 - Narcian *4: Green Axe Tank (Arthur)
3 - Robin F *4: Gronnwolf Mage (Anti-Cavalry)
4 - Palla *4: Red Sword
Essential:
Anything capable of killing four Cavalry Units.
Chapter 1-4: Blade and Dancer
Team:
1 - Lilina *4: Red Mage (Sophia)
2 - Clive *5: Blue Lance Tank (Subaki)
3 - Olivia *4: Dancer
4 - Corrin F *4: Blue Mage Tank
Essential:
2 - Blue Tank
Chapter 1-5: Captive Princess
Team:
1 - Black Knight *5: Distant Counter Tank [Seal - Distant Def 1]
2 - Clarisse *4: Archer
3 - Ursula *4: Blue Mage
4 - Lissa *4: Healer [Seal - Spur Def 1]
Essential:
1 - Distant Counter Tank
4 - Healer for Tank
*If you're having trouble, watch Baka Jam's strategy from YouTube