Just to clarify some things (or emphasize on them since they've already been stated) Arcanist only gets access to Summon (Emerald Carbuncle) and Summon II (Topaz Carbuncle). Summon is considered a Caster Summon, and Summon II is a Tank Summon.
Scholar also only gains access to Summon (Eos), and Summon II (Selene). Summon for Scholar is considered a Healing Summon and Summon II is a Support Summon.
Summoner on the other hand gets access to Summon (Garuda), Summon II (Titan), and Summon III (Ifrit). Summon and Summon II fill the same role as their Arcanist counterparts, while Summon III is a Melee DPS Summon.
During the last Live Letter, Yoshida was asked if there would be anymore Egis and his answer as (unfortunately) no, not until there was a level cap increase. This means we may see Egis for Shiva, Ramuh, Leviathan, and maybe even Odin and Bahamut, but not until an Expansion more than likely.
As far as the original question goes, the storyline for Arcanists is exceedingly lacking in acknowledgement of your ability to Summon Carbuncle, they just sort of say "Good job, you can control your Cosmic Bunny. Come back in five levels." In fact you don't even need to complete the level 15 quest to get access to Summon II, they just give it to you prior to actually doing the quest, primarily because it's a tutorial on how to use the Topaz Carbuncle as a tank.
That being said, within the actual summoning animation itself we see the use of the aforementioned crystals, so it's safe to assume even if the quests don't mention them the game still shows them being used.
Scholar also only gains access to Summon (Eos), and Summon II (Selene). Summon for Scholar is considered a Healing Summon and Summon II is a Support Summon.
Summoner on the other hand gets access to Summon (Garuda), Summon II (Titan), and Summon III (Ifrit). Summon and Summon II fill the same role as their Arcanist counterparts, while Summon III is a Melee DPS Summon.
During the last Live Letter, Yoshida was asked if there would be anymore Egis and his answer as (unfortunately) no, not until there was a level cap increase. This means we may see Egis for Shiva, Ramuh, Leviathan, and maybe even Odin and Bahamut, but not until an Expansion more than likely.
Quote:Q8: Are there any plans to implement additional egi?
A8: If we were going to implement additional egi, it would be when we raise the level cap.
As far as the original question goes, the storyline for Arcanists is exceedingly lacking in acknowledgement of your ability to Summon Carbuncle, they just sort of say "Good job, you can control your Cosmic Bunny. Come back in five levels." In fact you don't even need to complete the level 15 quest to get access to Summon II, they just give it to you prior to actually doing the quest, primarily because it's a tutorial on how to use the Topaz Carbuncle as a tank.
That being said, within the actual summoning animation itself we see the use of the aforementioned crystals, so it's safe to assume even if the quests don't mention them the game still shows them being used.