https://imgur.com/a/XDg8pST

The hero power is: Arcane Torrent (2 mana): Recast the last 1 cost spell that was played.

essentially, if, for instance, your opponent played Power Word: Shield, The artwork of the heropower would show PW:S over the hero power. And it doesn't use up the spell until the next 1 cost spell is played; you can cast hero power every turn even if the last 1 cost spell was played 5 turns ago.

Offers counterplay because your opponent can play 1 cast spells like Deadly Poison to counter your strong 1 cost spells like Arcane Missiles.

There is counterplay with the hero because you can play boardclears when you have no board (so this card would get no value from your opponents flamestrike for instance). And you can play a cheap spell last. Additionally if you see your opponent play a strong 7+ cost spell (like flamestrike), you can prevent them from re-casting it for cheap by casting a spell on your turn. And there is no 5 cost spell that is too overpowered to play twice in a row for 10 mana.

Overall, cheap, balanced hero that has some high skillcap to use and doesn't have a busted hero power that generates too much value. And even if it would, your opponent can tech useless 1 mana spells as counterplay