Deck Recommendation

Strategic Assessment

Asgardian Deck Basic Strategy:

Increase Thor and Hogun's Armor. They can convert Armor into Power in combat.

Pros:

Good at defense; can quickly gain the upper hand over opponents whose Power isn't strong enough.

Cons:

This deck's Power is concentrated in few main cards. If these cards are defeated or fall under your opponent's control, the deck loses all its potency.

Early to middle stages:

Get a Star Level 2 [Fandral] in the first two turns and use his self-enhancement ability to add him to your Asgardian front line.
Another way to add him to your Asgardian front line is by acquiring [Hogun] in the two turns during which the Lv. 3 Shop is available. You can gain an early-stage advantage with the Armor-boosting effects of [Jane Foster], [Shuri], [Korg] and [Thunder Defense].

Late stage:

[Thor] can be purchased from the Lv. 5 Shop.
Increasing [Thor]'s Armor is equivalent to increasing his Power. As long as he has high Armor, he can defeat all opponents single-handedly!

Ideal Front Line

Throg: If he's equipped with [Mjolnir], when dealing damage, his effects will also be triggered.
If you don't have [Mjolnir], [Hofund] works too.

Thor: Equip him with [Mjolnir].
The core card in this deck. If Thor has low Power, equip him with [Mjolnir] to increase his Power. If he already has high Power and Armor, you can give him equipment that grants "Guardian" instead, such as [Captain America's Shield] or [Asgardian Shield].

Valkyrie: Equip her with [Gungnir]
If you don't have [Gungnir], give her other Support equipment.

Hogun: Equip him with [Captain America's Shield] or [Asgardian Shield]
If he has a high Star Level, Hogun can be used as a Guardian character.
If you don't have [Hogun], you can replace him with other Guardian characters, such as [Guard Army of Asgard].

Hulk
Provides an Armor aura, increasing Throg, Thor, and Hogun's Armor.

Singles

Thor
 
When he loses Armor in battle, he gains an amount of Power equal to the lost Armor. At Star Level 4, he gains double the amount of Power instead!

During Preparation Phase, you can increase Thor's Armor by acquiring [Jane Foster], [Shuri], or [Korg]. During battle phases, use [Mjolnir], [Lady Sif] or [Hulk] to boost Thor's Armor.

Hogun
 
A less powerful Thor alternative.
A Super Card Hogun is strong enough to be part of the final front line. He makes a fine Guardian, at least.

Throg
 
His "Iron Will" effect helps him use his Power more efficiently.
Equip him with [Mjolnir] or [Hofund] or use him with [Lady Sif] to deal extra damage.

Lady Sif
 
Can boost the Armor of characters on both sides by a considerable amount.
Can take multiple actions when combined with Thor's Super Hero Skill.

Jane Foster

Can boost Thor and Hogun's Armor/Power.