This dirty deck is very strong right now and there are lot of similar variations going around on ladder! The very basic way to play this deck is to play the Royal Giant then play units behind him to support him and not try to keep him alive as long as possible. The furnace should be played centrally, the constant flow of the fire spirits can be extremely annoying to deal with and often will bait out a spell allowing you to stack up more units behind the royal giant. This deck is also pretty defensive the guards work great at defending princes, graveyard or even pekkas which can be a nuisance for the RG user. The fire spirits and ewiz (spawn damage) are you main splash damage units and they synergies very well at dealing with those annoying swarm decks or even helping you take down lava pups.
This card hasnt been used very much since his release however I like to use him to tank damage or to take out swarm units that could pose a threat to the Royal Giant.
This was extremely annoying before the balance changes and we’re all hoping that the reworked royal giant will improve this! It can no longer snipe buildings like it could before. However this card now does more DPS and the barbarian barrel is a great card to use to tank some damage allowing the RG to get a few extra hits on their towers or buildings.
Lightening is your heavy spell and can offer you a lot of value or even take down elixir collectors or reset inferno towers or inferno dragons.
Early game try to figure out what your opponent is playing. If they start with an elixir collector then ideally you should lightening th pump and the tower. However if you don’t have the spell in cycle then you can pressure with the RG at the bridge or simply just play a furnace. Against most archetypes you will be playing the RG early game to chip away at their tower and see how they respond and defend against your pushes.
Later game you will now know what deck your opponent is play, for example if they have a best down you should wait until they play their tank then apply pressure opposite lane. You can also start to use hpmore support troops either behind or in front of the RG depending on what deck they’re running. Try to bait out their spell before hand to avoid giving them lots of spell value or splash damage value if they have units like wizard or executioner. Lightening is a great to help finish a game off just make sure you remember it targets the highest HP units in its radius so can be easily distracted. Also I recommend taking all spell value you can especially if you can damage their tower too during double elixir.