-Extremely Long Range
-Usually guaranteed tower damage
-High Damage Troops
-Usually needs supporting troops
The Royal Giant is special in its own way. It is the only troop in the game that can hit enemy buildings without taking damage, due to its long 7 range. Mastering the Royal Giant can definitely get you into Arena 8 without paying a dime.
To know how to use any troop, you need to understand what counters it. From personal experience, 9 out of 10 times my opponents play either minion horde or barbarians in response to my Royal Giant, and that other 1 time is a pekka/mini-pekka. With this understanding, I am already expecting my opponent to play 1 of the 2 cards, and am ready to respond. To counter barbarians play your Royal Giant with a Valkyrie or a Wizard. I always keep my elixir above 3 if i know my opponent has a minion horde, with arrows already pre-selected and pre-aimed. This saves me about a second of valuable time, which may not seem like much, but usually results in a couple more hits onto the tower.
The Royal Giant is best played with supporting troops like goblins or archers. An exception to this is if you know your opponent has no answer to a lone RG, or if the enemy tower only needs a couple hits to kill it. Placing a Royal Giant at the bridge with support troops behind it usually guarantees some tower damage.
One thing that you always need to be aware of is Inferno Towers. A well placed inferno tower will kill your Royal Giant and stay alive, giving your opponent an elixir advantage. To counter this, you either have to zap/freeze the inferno tower, or make sure your Royal Giant isn’t targeted by placing cheap melee troops in front of it (goblins, skeletons, etc). Keep in mind all units in the game always hits the closest possible target.
Royal Giant, Elixir Collector, Arrows, Fireball, Spear Goblins, Ice Wizard/Archers, Barbarians, Minions
A deck that has been rising in popularity, it aims to protect the Royal Giant with cheap cycle troops. Barbarians are mainly used defensively against hogs/opposing Royal Giants, while fireball/arrows are used to deal with swarms of troops, minion hordes, or buildings. Elixir Collector is critical in this deck, as it allows you to cycle a card while gaining extra elixir.
Royal Giant, Arrows, Spear Goblins, Archers, Minions, Hogs, Barbarians, Wizard
Another cheap cycle deck, but with another win condition. Oftentimes your opponents overcommit to killing your Royal Giant, and placing a hog in the other lane can lead to devastating damage. Royal Giant is best played with Wizard, while minions and barbarians are used defensively.
Royal Giant, Arrows, Inferno Tower, Princess, Ice Wizard, Barbarians, Spear Goblins, Minions
A deck usually found in high arena 8 due to all the legendaries, it plays out similarly to the first deck. However Inferno is included to counter other Royal Giants, while princess and ice wizard are usually good value no matter how you use it.