Viking: Battle for Asgard/Purchasables

Runes
Runes are elemental powers that give Skarin the ability to enhance his weapon and his allies weapons with the element of choice. This power can only be unleashed if the power bar is at a significant level, and while the effects exist, the power bar will be drained until it is empty. Once enabled, elemental powers cannot be stopped until the bar is empty! Note that you can stop the power bar from draining if you do something where Skarin is forced to put his weapons away (like opening a chest or door). There are three runes that can be upgraded four times over the course of the game:
 * Fire Rune: enchants weapons to ignite foes on contact (dealing additional damage). When focused, a flamethrower-like flame extends from Skarin and his blade.  Skarin cannot move when using this power (stop, then use it again if missing the target), and it can be held to deal additional damage.
 * Ice Rune: enchants weapons to freeze enemies. Once frozen, an additional attack will shatter them.  When focused, Skarin pounds the ground, raising ice in a small circle around him and freezing all enemies who get touched by it.
 * Lightning Rune: enchants weapons to shock enemies (dealing additional damage). When focused, Skarin extends entrails of energy to one target, lifting them off the ground and frying them to a crisp.

You'll notice that champions have a resistance to these powers - even though they take additional damage, it is minimal. However, the freezing effect of the ice rune is useful in gaining additional attacks on the target, since they move slower or freeze altogether temporarily.

Battle Items
There are three items that can be used during battle: throwing axes, health potions, and fire pots.

Throwing Axes
Throwing axes are very powerful ranged weapons that cannot be aimed vertically. Only 10 of these can be equipped at a time. The problem with this weapon and the fire pots is that it cannot be easily aimed. However, they much more powerful than Skarin's normal weapons and thus using them properly can give players the upper hand in battle. They are not useful in large scale assaults, since Skarin can attack multiple targets, collect orbs, and unleash elemental powers while in melee combat.
 * Equippable: 3

To aim a throwing axe, rotate Skarin so he is facing the target, then when the correct target has the above it, press the button to throw an axe. Objects and other enemies can get in the way, so make sure you have a good line of sight to your target.

On Garcliff, these will be upgraded to "Chieftain Throwing Axes" - dealing more damage when striking a foe.

Fire Pots
Fire pots, or fire potions, are grenade-like weapons that deal damage in a small radius around the target. Only 3 of these can be equipped at a time. These are only available on Garcliff and Isaholm.
 * Equippable: 3
 * How to Unlock: release the vikings at the brewery on Garcliff.

To aim a fire pot, use the same technique for a throwing axe but press instead.

Health Potions
Health potions revive a small amount of Skarin's health when used. On Garcliff, after taking back the vinyard, the health potions will be automatically upgraded (even the ones in your inventory) to increase the amount of health restored.
 * Equippable: 3

Maps
Maps are permanent upgrades to the minimap. Each one makes a specific object type appear on the map as a yellow dot. The three maps are:

The only problem with purchasing all three maps is that you cannot distinguish one object type from another when looking at the minimap.