Arrows and Fireball are used much like in any other deck, but you have a lot of freedom to save them for when it really counts.
Use this near bridges on the opposite sode of where you are moving towards, that way you have your units taking out enemy cards and you have a solid defense near your blind spot. The Tesla will hide underground until an enemy unit passes over and then attack. The Tesla is a powerful defense card are well, especially when its on the field already and you are focusing on pushing your units forward. You can also use Barbarians as a good defense measure if you have an enemy Giant or other pwerful card moving towards your towers. Seapr Goblins and Archers do what they do best from a distance and are good defenders against incoming attacks.
Giants and Barbarians will be powerful damage dealing units, while the Witch can do the same while summoning skeletons to the field. This deck focuses on having a powerful tank card push through enemy defenses straight to a Tower.