i got a graveyard in clan chest, can't seem to use it at all.
What's the secret? i just get countered every time with something like valk / minions
I'm tipsy and avoiding something. Sounds like a good time for a long post!
A few things:
1) you need a tank or mini tank (knight/valk/ice golem/baby dragon/etc) to soak tower shots since tower one hits skeletons. Most GY decks have two tanks or mini tanks.
2.0) need at least one spell to take out their counter. I recommend log or zap as a second spellZ Zap, arrows, fireball and poison are your main options for pairing with GY. Freeze is also viable, but less commonly used. Poison is used by most pros, even in most GY cycle decks. It's a heavy investment (11 elixer if your tank is a cheap ice golem... 14 for giant). So, timing is everything. Gotta get the combo going. If you need to defend another lane, then do it. Start the combo over in a moment. That's why it's nice having two tanks.
2.5) poison got popular with its buff a few months ago and I recommend that as your spell unless you're wanting a crazy GY cycle, which is a little weaker but fun to play. When running poison, this is how you play it. Your tank is on the bridge and you drop GY. Tank crosses bridge before skeletons spawn and is targeted by tower. You're hover poison already, but waiting for them to drop their counter. Drop poison on the counter (or, optionally, sacrifice troop damage for collector damage if they have one). If it's squishy like minions, gob gang, dart gob, archers, etc then it dies. If it's a knight or valk, it survives but is weakened. But if their counter is valk, then you may have goofed - avoid playing GY when they have it in hand. If they're smart, they'll never play it until you cast GY once you have it it. In that case, build huge pushes up and play really fucking well... it's going to be a game that goes to OT, so play solid defense too. In general, GY is strongest when their best counter is out of hand. Their next best counters are either weak to poison, or shit defending GY.
3) when you have one of the opponent's towers down you can perform a quick strike that's hard to deal with, especially in double elixer. Cast GY on the tower. Opponent will be reacting to cast a counter. Drop your tank immediately after in the pocket - the corner spot on he enemy's side. It soaks damage from both towers. Cast your spell to deal with their GY counter. And win the game, hopefully.
4) YouTube "splashyard deck" if you like tornado. It's a great GY deck that runs baby dragon and bowler. Along with the option to poison, you can also tornado the GY counter and the tank counter directly on top of the tower do that your dragon or bowler deals splash damage to troops + tower + skeletons on the other side of the tower go to town.
Edit: 5) never cast a naked GY (GY with no tank) unless its panic time and there's 400hp left or something. Only do it if absolutely necessary and add every spell you can. Otherwise, don't. Build up a good push or don't use it.
6) don't cast your GY too close to their king tower! An activated king tower wrecks GY with double the towers locked on it. If you ever get one tower into range of a spell killing it, focus on the other!! You don't want the king tower helping.
/edit
Have fun! I hate myself so I play mortar, but GY is very powerful at level one below 4K, and it can actually do quite well as a low level card at high trophy counts, so it's one of the best legendaries to have in a ladder deck as a f2p (or very little money to play) player.