Quoting si1foo, reply 24i use for tb when fighting a qot fireball taking down the first one firenova then rain off ice then frostnova then back to fireball again then a little dps dmg if she is still alive then ill do fire nova and maybe a fb if she is running
fb has 4 sec recast
ice has 10 i think
fire nova 10i think
frost nova i think is 15
Congratulations. You've done about 2.5 k damage in 10 seconds. I just regened 1000 with sedna and healed the remaining 1500 for about 600 mana. Or with QoT you broke my shield, which I quickly replaced. You have not yet broken the second one. If somehow there were two of you doing a total of 5k damage in 10 seconds, she could just eat one of her minions for an extra 2500 health, she's at full health and has expended about 1.5k mana only.
You've accomplished nothing.
TB in particular is BAD late game which you would need to have in order to have these skills anyway. He, just like Erebus, must take advantage of levels 4-12 when they are very powerful. And even at those levels they cannot deal with a defensive player such as Sedna or QoT. Hell, anyone with a HoL can just disengage from combat, heal fully, and come right back in, assuming they weren't dumb enough to get into a situation where they would definitely die to Erebus (or TB).
Also, your cooldown numbers are way off.
That is true. I have noticed both TB/Erebus excelling in early game, which can help their late game if they get enough demigod kills to afford some nice artifacts/gear fast enough. However, playing as Erebus, if the other team is not giving up kills easily and can keep my gear selection down, when the late game arrives it becomes very difficult to engage them successfully thanks to different characters abilities and stats scaling.
The only thing I would contend is that in the early game, a decent Erebus can kill/push a average/good sedna off a flag, unlike UB/TB/QoT where i notice my partners often cannot win the attrition battle with her in the early game, though if she pops a small potion toward the end and the Erebus cannot match and has exceeded mana, its likely over for him.