So I was toying around with Deathwing's talents in regards to his ranged form, and noticed some weird numbers with his W (Lava Burst) vs Heroes when the Heat Wave talent is picked.
Basically, at level 4, the burst damage of Lava Burst is 35. Against Heroes, that's increased by 100% due to DW's passive, so it would be 70 damage. Heat Wave reads "...increase the explosion damage of Lava Burst by 125%." I would think, "Okay, I'm doing 70 on the burst, increased by 125% that should be around 150 damage, right?" Wrong. It's 114 to Heroes.
This confused me for a while (no math classes for about three years, oof) until I realised that the damage bonuses that were being applied to that base 35 damage, weren't multiplicative, but additive. I assumed with the passive (+100% bonus dmg to Heroes) and the talent (+125% damage), that would mean ((35*2)*2.25) or ((35*2.25)*2), both equaling 157.5. In reality, the game runs it as:
(35+[35*1.00]+[35*1.25]) = 113.75 (rounded up to 114).
Also note that 114 is a ~61% increase from 70 (the untalented burst damage vs. Heroes. Comparatively, 157.5 is a 125% increase from 70.
So, while the math technically checks out, Heat Wave is effectively only increasing your W explosion by ~61%, not written 125%. This also translates into less healing than expected when combined with Dragon Soul, at level 1, which makes you heal 150% of W explosion damage dealt to Heroes.
The reason I brought up his wack base damage is because I cannot for the life of me figure out why they made his base damage low, and say "double damage to heroes," instead of "half damage to non-Heroes. If they did it that way, assuming his real damage output didn't change, that would mean that the base damage Heat Wave is adding that +125% to would be 70, therefore making the talented explosion do 157.5 (an actual 125% increase in damage).
And yes, this would mean that the PvE explosion damage is now 122.5 instead of 79, and increase of 43.5 damage at level 4. For reference, warrior minions have 1006 health and wizards have 503.
I'll stop before I go too much farther off topic, but the point I wanna make is that this wack base damage makes his talents feel extremely disappointing in spots. More disappointing than "Deathwing does half damage to non-Heroes" would be.
Edit : This same stuff applies to other general % dmg increases, like Dragon's Ire (25% more damage to all of DW 's damage while at 3 or less armor plates): it ends up being about a 12% damage increase vs. Heroes. Infernus is really a ~38% increase in Q damage as opposed to whopping 75% it reads. Burn Beneath My Shadow only increases periodic damage by about 40%, instead of 80%. Arrival of a God at 20 increase landing damage by "400%", but it's effectively 200% against Heroes, going from 219 to 658 at level 20. Destroyer's Rampage increases DW damage by 40% after landing in melee form; this means his auto's are 40% stronger, while his abilities are only 20% stronger. Obviously, Fire and Fury at 13 is the full 30% increased damage on autos vs. slowed Heroes, since his passive isn't involved.
TL;DR: % damage bonuses are additive, not multiplicative, and on Deathwing that means less dmg/healing because of his silly low base damage and framing of his passive.
