Basically everything that gives +X ATK doesn't work in Giant form - or doesn't work properly. Here's what I tested so far.

Godslayer "18018" - Attack doesn't add up, making the card null

Skilled Strike "09037" - Same as above

Mean Swing  "06015" - Same as Above

Rapid Growth "13005" - Cannot be used while in Giant Form (it should work in giant form, there's no rule against it) - Can't split the damage if used from Tiny form (the only actually usable way at the moment)

Also, even though I haven't tested it yet, I'm pretty sure the same bug applies to +X THW cards, because the interaction window to split damage\thwarts happens just one time, when the card is being exhausted to use the basic power. 

A possible solution could be to query the Split damage\thwart function at the end of every Interrupt\Response.

Hi @NovaHiros,

Thank you for reporting the bug regarding card “13001c” in version 0.5.9.4.

In the normal attack resolution flow, you select targets and then calculate damage. However, for “13001c,” you do not calculate damage; instead, you “assign” 1 damage to each target you select (similar to assigning indirect damage). We implemented it this way because the effect of “13001c” modifies the target selection process.

When a card like “18018” gives you additional ATK, you have already selected your targets at that moment, and the engine only assigns damage to those targets. While the ATK does add up, you cannot assign that ATK to any target because you have already completed the target selection step.

We cannot add a window for reselection of targets, as that would introduce additional issues. However, we will consider your suggestion to query the Split damage/thwart function at the end of every Interrupt/Response.

Please note:

1. If your ATK is added before target selection, as with card “01057,” the resolution will work as intended.
2. This bug also occurs with card “29033.”

Thank you for your understanding, and we appreciate your feedback!

Even though  probably unnecessary, I can confirm that the same bad interaction happens with THW events like Making an entrance "20013", which is very unfortunate because it is  ultimately breaking the whole Wasp character.

I'm glad you're considering my suggestion, fingers crossed for a fix!