[//guide]

Prompted by /u/razorxscooter on Discord, I've done some testing into this elgif and how it interacts with various unit abilities. The Elgif's main effect, for the unaware:

• Adds a Burst Heal effect to the equipped unit's SBB (Heals for 3500-4000 40% Caster REC 100% Recipient REC)
  • Of note is that the Elgif only procs when using SBB. Some units might become more interesting if it procced on BB.
• It also adds some other passives that don't really matter to the experiment including ailment null, crit null and 30% ATK/DEF/REC when over 50% HP.

Results follow; if you have a surplus of Emgifs you could try testing for yourself as well.

1. If the SBB contains an attack with a hit distribution, the elgif Burst Heal will attempt to match that hit distribution.
2. If the SBB contains multiple attacks, the elgif Burst Heal will attempt to match the hit distibutions of all attacks that occur on the first frame the unit calculates damage
   • In other words, looking at a unit's frame data, the heal will match the distribution of the attack with the lowest Effect Delay. If multiple attacks have the same Effect Delay as the lowest present, the heal will match both simultaneously.
3. RT SBB effectively have a hit distribution of 100% on each hit; however, rules on what the Elgif considers an additional attack mean that an RT attack can only proc Wondrous Aegis once.
   • RT effects typically have extremely low hit delays, so you'll see it proc very early within the attack.
   • As a side note, the only RT SBB I had access to was Eric's due to the multiple attacks rule noted above. At any rate, he only procs a single heal tick when he uses the Elgif with his RT SBB.
4. If the unit doesn't attack, the Elgif procs on frame 0 of the SBB unless another burst heal is present, in which case it procs on the same frame(s).
   • The elgif heal will proc independent of the main heal.
5. The heal will always be AoE, even if it takes its hit pattern from an single target attack

The first, third and fourth rules only really determine what the heal looks like on screen, without affecting the heal amount.

However, the second rule means that units with multiple attacks that share an effect delay will heal significantly more than expected. In most cases where this happens, the unit's healing output with the elgif effectively doubles; this happens because the elgif heals according to distribution, and the sum distribution of two attacks is typically going to be 200% (there are no relevant exceptions).

There are no triple attack units which can cause this bug to create a 300% heal due to the timing on the ES of the VA units (1 frame before their other attacks).

This bug is also the explanation as to why Gabriela's Burst Heal SP option heals twice the expected amount, and causes her to heal twice the expected amount with the Elgif as well. Or even quad heals with Elgif SP (totalling 400% Recipient REC 160% Gabreila REC 14000~16000, a guaranteed full heal with any OE HP->REC Convert)

Finally, there's a somewhat strange interaction when using it with units that already have burst heals; if the unit has an attack and a burst heal, the elgif's healing will follow the distribution of the attack regardless of how the other heal performs or even when it fires (game prioritizes attack patterns to determine the Elgif's healing pattern). This can be seen obviously on Linasera, where her own burst heal procs on the first frame of her attack, while the elgif's burst heal follows the attack pattern.

Conclusions

To boil everything down, here's some quick bullet points (mostly a re-iteration of the above content):

• Wondrous Aegis will follow the attack pattern of a unit's first attack, if it has one. If it doesn't have an attack, but does have a unique pattern for a burst heal it already has, Wondrous Aegis will follow that instead.
• Wondrous Aegis procs independently on units that already have burst heals, which means you get the full REC bonus on both heals.
• If a unit has multiple attacks that share an effect delay, Wondrous Aegis will follow both patterns and double its healing output.
  • This doubles healing output on the following units that come to mind right at this moment, with likely more besides:
    • Zeis, Natsu, Lasswell, Durumn, Erza, Fei and Fang, Gabriela, Nyami, Savei
      • Stops working for Savei vs Light units in Guild Raid due to his Guild Raid ES (additional attack on Light units during Guild Raid) which triggers on frame 0
  • It's important to note that due to how they're coded, no JP units trigger this bug/effect. Alim generally put the majority of procs with different effect delays on attacks even when it had seemingly no effect on gameplay, which prevents this bug from occuring on their units.
    • Even then, players in the JP server have no way to trigger this bug even if their units did act this way. They have no double attacking units that can burst heal inherently and no wayto add it to units like global can. Their units avoid the bug despite JP never seemingly having any case for bugs to be caused by multi-attacks.
• A possible use for the Elgif in content with Damage Reflect is placing it on a unit with a heavily delayed burst heal and no attack, such as Elimo. This will almost double her healing output while matching her delayed heal frames, heavily improving survivability after Damage Reflect.
• Also consider that there are at least two (potential) iSBB units that get double healing from it: Nyami and Savei.