League of Legends (LoL) Question: What do you think about Support Galio?

If there's one champion in the game I know little about it's Galio. Things I do know:
- Bulwark is great
- Excels against AP laner
- Mana hungry
- Only hard CC from ultimate, which has a long cooldown

At bot lane you're usually dealing a lot with AD instead of AP, so he's not in his element. Furthermore I'd say he's too item-reliant and brings not enough reliable CC to the table to be called a good support pick.

Like others mentioned, it could work. But I would certainly not recommend it.

Cons

• Only hard CC is ultimate
• Main damage abilities are skillshots that can have the side
  effect of pushing the minion wave.
• Melee autoattack
• Heavily oriented toward countering magic users
• Only has built in sustain for himself, but only if his shielded target is taking damage
• Ult is a channeled ability so common supports can interrupt if they can stay out of the taunt.

Pros

• Has a targetable shield
• Has speed-up
• Has slow
• AoE taunt

It can work, but there are champions like Annie that do everything Galio does and more.

He's extremely fun. The biggest thing is getting accurate with Resolute Smite, which can be difficult to learn. He works well both with poke marksman, as well as those with powerful all ins. He's versatile, he has the capacity to build damage, as well as building tanky. The biggest problem with him is his mana hunger. He goes through it very quickly, and can't do a whole lot without it. He's also melee, which makes Relic Shield even better on him, but it means that your sole form of harassing is Resolute Smite.

When possible, play him with Kalista, as their ult synergy is almost unfair. :)

I played some games as Galio as support. There are few adc who does very well with Galio like Miss Fortune who can fully apply her ultimate if Idol of Durand will be landed properly or Kalista with her ult giving insane positioning possibility to use Idol of Durand.
Bad thing is there's few champions who can interrupt his ultimate easily like Leona or Braum, what may force you to buy Banshee's Veil when you should buy more suitable items for support.
Good thing is that few viable items for support have magic resist like Locket of the Iron Solari and Mikael's Blessing - and both fits very well into his kit.
If you will build Galio in way like other support tanks I think he should work very well this way.