Should probably target the creature in the graveyard.

Needs to cost more - this is cheaper and better than Resounding Silence's normal mode. may well be enough though - exile attacker + bonus.

If you do target the creature card in the GY, you probably want "Return up to 1 target", otherwise it can't be played if your GY is empty.

­Resounding Silence is a common, whereas this is an uncommon. I was guided more by Path to Exile when making this card. That is to exile any creature with its controller getting the bonus. This only exiles an attacker which limits its use and gives the caster a bonus that may or may not trigger. You are right about it needing to target, but leavingit as specific targetting brings it in line with the ability and wording of Sun Titan which is what I was thinking of when I designed the second half.

With the current wording, it still can't be cast if there are no targets in the graveyard, because you need a target even though the text says "You may". If you want it to be optional, say "up to one target"; if you don't, remove the "You may". The comparison with Sun Titan is misleading, because you can still cast him even if his ETB ability can't find any targets, whereas you can't cast an instant or sorcery if you're missing targets.

And I really don't think you want to be using Path to Exile as a baseline. That card was exceedingly pushed relative to normal power levels. Rarity isn't generally a good defence of power level either, except perhaps in the case of mythic rarity.

I agree with how crazy strong Path to Exile was. I wanted to try to make make a somewhat more balanced version of it that rewarded the caster.. Part of Resounding Silence's cost was the cycling ability which, whilst hard to pull off, doubled the power of the card. Should this be or or if I drop it to cmc 2 or less would it be better?

I think I agree with Chris that is the right cost for this effect. If you really wanted to make it CMC 3, you might be able to get away with , as in Wing Shards.

White normally doesn't return creatures from the graveyard to the hand. Twilight Shepherd, Sigil of the New Dawn and Enduring Renewal are the only ones and the latter two do so only when the creature dies (Twilight Shephered returns all cards). White returns creatures from the graveyard to the battlefield. Still, a cool design if you think it's okay pie-wise.

You're right, even the inspiration card Sun Titan returns to battlefield. Change made.

I tend to be somewhat overcautious at times, overcosting or weakening abilities. (much easier to make stronger than weaker).

Don't worry. As it is, it is a good trick (and card advantage) but at uncommon it makes it as okay as a full Dispense Justice. Powerful if done right, but a bit harder to do right than one might think.

One thing I'd do, though, is make the cost . Splashing for this seems a bit wrong since there are two very white effects.

changed cost