We should get more offensive summoners

For me, the only offensive one is ignite, and maybe red/blue smite. People can argue that heal, barrier, and exhaust can be offensive, but I'm talking more of a damage dealing summoner. I hate being limited to a DOT to try and outtrade midlane, why not give some more options? One suggestion:

Lock: Applies the grounded debuff to your target, and for each 10 units the target moves, they take 5-40 damage for 3/4 seconds. This could apply some nice advantages if counterpicking or for adcs, but may need to be tweaked.