Mighty Shield should read:
Prevent all damage done to this Pokemon by attacks during your opponent's next turn. This Pokemon has no Ability and cannot attack during your next turn.
The other Aegislash feels OP despite the cost, especially with the amount of energy acceleration there is today. That or it feels like way tooo much damage for the Pokemon in relation to its other cards. It also should read:
This attack does 300 damage to 1 of your opponent's Pokémon. Discard all [M] Energy attached to Aegislash.
Prevent all damage done to this Pokemon by attacks during your opponent's next turn. This Pokemon has no Ability and cannot attack during your next turn.
The other Aegislash feels OP despite the cost, especially with the amount of energy acceleration there is today. That or it feels like way tooo much damage for the Pokemon in relation to its other cards. It also should read:
This attack does 300 damage to 1 of your opponent's Pokémon. Discard all [M] Energy attached to Aegislash.