the handling of the ball, the ruck, maul, and the fact it's one of the toughest games on the planet. I would suggest you watch it more thoroughly preferably with someone who is knowledgeable about the game.
Its a great sport, come on England.
- accuracy of passing
- accuracy of kicking
- spotting space to use for kicking to touch or space
- timing runs to avoid offside
- spotting progression opportunities
- accurate goal kicking
- strategy
- execution of set pieces
- phase implementation
- accurate tackling
- evasion of tacking
- winning rucks and mauls
- drop kicking
.....I could go on
many more skills and much much tougher than soccer. If you have to ask such a stupid question then you will not be capable of comprehending the answer but hey ho, I gave it a go.