Lina innate math and why you should buy pipe

TL;DR: Lina's innate is supposed to deal 40% splash damage (70 / 175). However, this splash is treated as if each hero hit by her AOE spells. If you hit 3 heroes such as in the gorp video, this means the splash is 120% to all other units. If you buy pipe, each instance of damage is reduced which makes it deal significantly less burst.

Total damage of Q+W with shard and 62% spell amp is 1312 (vs 25% resist). With 120% splash, this becomes 2890. With rs roar +25% this is easily 3600.

How do you reduce this? Buy pipe. This reduces the damage everyone takes and combustion is also reduced by magic resist.

3 targets hit by max items Q+W will combust for 1500. Just with pipe aura, this is reduced to 1330. If you actually cast pipe, this is reduced to a whopping 200 combust damage.

Now if you're the Lina player, how are you supposed to cast spells? Combustion actually only procs if the hero receiving the magic damage is alive after the damage is dealt. Therefore, to deal the most damage, use Laguna on a full HP target in between all enemies (this will splash 400 on everyone). Then your shard buffed spells can be used to splash on everyone else which will have the highest chance of it dealing combustion on all other heroes.