LoS and spells

[Pudge]

If you are inside and the caster begins casting at you (which means the see you) you can run around a corner and it will reduce the range they will be able to cast. So if you get far enough away, and are also breaking their los, you can avoid the spell.

Water also breaks los and will prevent the cast from hitting you - both inside and out - regardless of distance from the caster. So get near a body of water and if you're submerged while they're over the top then the spell will go off, and waste their mana, but you will not be affected by it. Same if they're underwater but you're out.