Its annoying how useless team avatar is.
'Ok I think its best we try to stop the weapon ourselves to prevent a war'
.
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'Oh shit they shot at us retreat. Them fighting back was totally unexpected'
Did you forget the part where they thought they were going to be sneaking into an army that still had a week's worth of preparations to go through to be battle-ready, so them running into an entire mobilized army by surprise like they did was never part of the plan.
Not to mention they thought they were going to sabotage a cannon-type weapon that would be transported by rail and had only the ability to adjust its aim vertically, apparently - not a 25 story tall fully articulated mecha-monster with the cannon attached to it in a way that eliminated the aiming deficiencies and gave it a far superior firing vantage.
It was supposed to be a stealth operation on an unsuspecting military. Instead they ran face-first into a marching military force with weaponry they hadn't even imagined yet.
You can make anything sound stupid if you don't pay even passing attention to the story and then try to blame it on the writing when you don't know what's going on.
Why has he not just made the feet under Kuvira lava?
It's such an OP technique it ruins everything. Probably my least favorite thing from book 3
The Colossus is 25 stories tall. I really doubt the "pools" that Bolin's Lavabending creates are even a full "story" deep.
Also, the Colossus is made of platinum, which has a melting point of 3,215 degrees Fahrenheit.
Lava ranges from 1,290 to 2,190. Significantly below what you'd need to damage it though the heat.
Even if we assume Lavabending isn't true to its name and actually bends "magma," the hottest magma recorded is still about 800 degrees too cold to do anything at all.
Even if Bolin could create, say, a pool of lava 10 stories deep, manage to bend it underneath the Colossus *and* hold it still long enough for it to sink to the bottom, it'd do nothing more than make it stationary, at best and slow it down, at worst.
Now I doubt the Colossus is heat *shielded.* If Bolin could submerge it completely then he could take out the crew through convection heat and make the Colossus inaccessible to anyone else, at least for a long time.
But, that's *ridiculously* outside the scope of Bolin's abilities. Lavabending is extremely rare, but it doesn't make him some kind of exceptional super-bender - just one blessed with a niche skill.