The first one comes from the combination of the Giant Skeleton and Witch/Wizard.
Go to the second combo. It is the combination of the Giant Skeleton and one of the damaging spell, Lightning, etc.
If you find the enemy’s counter to the big guy is only a defensive harmful building such as the Inferno Tower, Bomb Tower, Tesla, etc. The use of the Lightning spell is quite impressive to those building. As a result, Lightning is considered to be the most efficient in destroying them and assisting the big bone in delivering the bomb.
Third one, with the Valkyrie.
Due to it is a situational combo, when you find the troublesome comes from any ground troops especially the rangers, you can use Valkyrie to wipe them all. Soldiers such as the Archers, Musketeer, Wizard, etc., will be vulnerable against your Valkyrie. Most noteworthy, she is rather a tanky land troop which can also be a support in delivering the Giant Skeleton’s bomb to the enemy’s tower.
Fourth, combined it with the Balloon.
With the epic spell card, the Poison
Cheap but no cheapo
Alongside the Inferno Dragon
Walking with the Mega Knight!
Sparkling sparkle from the Sparky