Use Glacial Shard on turn 1 or save for synergy?

Solution 1:

This depends on a lot of factors. Playing cards on turn one can be valuable because it gives you immediate advantage on the board. Freeze is valuable because it lets you prevent your opponent from taking the board.

Generally, I'd say you should play the Glacial Shard if your opponent can't easily deal with it, or if you have plays for future turns. Playing it against Mage on turn one is often silly because they can hero power it without spending any cards; however, if you have a hand like the one in your picture, you should play it anyways. This way, the mage will spend their turn hero powering instead of playing a threat, which gives you the advantage when you drop your Pyros. If you're playing a class like Warlock, however, you should almost always play the one mana card. Their hero power can't kill your minion, so they will have to expend resources on it; even though Mortal Coil is a great play for them in this situation, they're still spending their mana on that instead of on developing.

In your current situation, you should ABSOLUTELY have played the Glacial Shard. You're facing a Warlock and you have plays for the following turns.