Ward While Casting

Type: Enchantment
Subtype: Aura
Card text:
"Flash.

As long as CARDNAME is being cast, the creature it is targeting has Ward {3}.

When CARDNAME enters the battlefield, counter for each spell an opponent controls targeting it unless they pay {3}.

Enchanted creature gets +1/+1 and Ward {3}."

Expected rarity: Uncommon (U) or Rare (R)
Rarity Reasoning:
-Wordy card;
- May prove unintuitive to play against;
- Similar effects (Enchanted creature has Ward or Hexproof) at uncommon.

Innovation: Spell that protects the permanent or player it is targeting while it is being cast.
Choice of effects:
- Ward makes it weaker and less punishing than hexproof, making it cheaper.
- Ward allows Play Design to better tune the values and costs of the card.

Tentative cost: {1}{U}{U}
Cost Reasoning:
- While the effect was firstly intended for a multicolor card, the effect is essentially very blue, specially with the focus on countering and being a flash protection spell.
- Effects that grant Hexproof UEOT to the enchanted creature at ETB  and +1/+1 tend to cost {1}{U} at common. Considering the protection while the spell is being cast and the longer effect in trade of it not being Hexproof, an extra cost of {U}

Possible alterations:
- If too strong as monocolor, still usable as a 2 color WU, GU or even GW design.
- Also doable in white, but likely weaker than if blue.
- Could be UB, WB or WR if the ward and countering cost mixed paying life.
- Ward/Countering cost adjustable.
- +1/+1 removable or adjustable, although that could narrow the card too much or make it too much more powerful.

Innitial Name: "Veil of Warding"