It's actually not that great, especially if the enemy support has some kind of heal in their kit. She provides next to nothing as a support except for a pretty fast, non-damaging, skill shot stun that's blocked by minions. She has no presence in a team fight and she just can't do anything without any items, which she'll be deprived of since she's supporting, and this is regardless of the fact that she has % based damage.
Edit: Forgot about her Volatile Spiderling, it can provide vision, which is amazing for what a champion can do, but only for a few seconds, which still isn't enough to play her as a support.
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