Whale In Guardian Conquest

I will semi-agree with King here, the items listed here are generally good, but generic.

You do cover some good things. Prophetic and Thebes (not always or often built together) offer very high overall protections. You have high health sustain via Gaia and Renewal, some mitigation potential from Oni, and you do list one counter item (Spectral, which is great to recognize for anti-crit function). You also go the Heroism route, and the shield for teammates is nice.

But I would argue that you should probably choose just one of Gaia or Renewal, with a generally strong preference toward Renewal, as Gaia is technically a selfish sustain item and not really considered very strong of an item right now.

In most situations for a Support-type role (as you mention accompanying the Carry), you also don't provide other utility or counter options...no anti-heal mention, no Shogun's option to support the Carry's AS. No Magi's Shelter option to help teammates counter enemy CC, etc.

In most cases I wouldn't pick up chalices for a Support role. For recipes, I would consider Drumstick for a Solo lane function, but not for a Support. You should be getting Stew for that.

I also feel that the CDR is on the low side. You only have 10% in the standard build, outside of using a Potion of Power, which is not something you pick up until late game when you have an excess of gold (the power it provides isn't really something that does much for you, only the CDR).

Your relic choices are mostly selfish. I'm fine with Blink as a situational option since he can push enemies back with his 3, but Aegis should only be considered when there's a potential execute ability, and why would you not list options for Wings or Shell, which will support your Carry and other teammates?

In the end, I would probably drop Gaia, I would consider going only Prophetic OR Thebes, and that should free up space for 2 other items that you can fill with other utility.