Okey so I got the idea in HOTS, Abathur. I liked the idea, champion /hero who doesn't leave base and is a support. First I wanna say that I imagined this champion only for supporting so the skills are designed for support. The idea about support who doesn't leave base does sound odd and I know it probably won't work with everyone. (peeling)
I haven't came up with name but it needs to be like with the others voidborn creatures, xxx'xxx (if someone didn't understand, vel'koz, kog'maw)
for he's passive > he attaches himself to adc and if the adc dies you will fall off and you can be killed, you can still attach yourself to someone else after some delay but no, you are not immortal :) I don't know what would be the proper amount of hp and armor and mr in blob form.
Q > X (our nameless champ) places ward, the range would increase some when you level up the ability. This is just a suggestion !
At this point I wanna say that please, if you have better idea then don't be afraid to leave a comment, I need help with this champion and I'm sure there's people who also wanna support from void. Maybe our ideas combined will came up with something what Riot will seriously think about.
soo then W> you are still support and you can use your items, just from where the adc is so something like frozen heart or aegis of legion will work. Or mikaels, face of the mountain, frostqueens calms and so on. W active could be something like movement speed burst or gives attack speed.
E > fires a slime which stunns the first target and slows the rest.
R > knocks every enemy away from you to some distance, this skill could have little longer cd so you won't be able use it all the time, would be too op. Its like tristana ult but works on many targets.
help me improve this idea, maybe we can have support something familiar to this. ^^