Hey, well I didn't know where else to post this but...well here goes:

My questions are about items such as trinity force and sheen, where you use an ability and it triggers an effect that adds bonus damage to your next attack. While I am fairly certain that the effects from lich bane and sheen do not stack...what about trinity force and sheen/lich bane? Since one is based off of attack damage and the other is based off of ability power.

Furthermore I have a question about dodge: simply, what is the cap for dodge? Or is there one?

About the items - no, none of them stack. They all count as variations of sheen :/ (to prevent abuses)

About dodge - while there is no cap, it doesn't stack straight forward as a stat. If you have two sources of dodge, and each gives 10%, you won't get 10+10=20. You will get 10%100 + 10%90 (the remianing) = 19%

So each source of dodge after the initial does not effect the global chance but just the remaining one. Thus, you can never have 100% =)

There is no cap to Dodge, but the more dodge you get, the less valuable it becomes.

Say you've got a Ninja Tabi, that's 12% Dodge right there. Get a Phantom Dancer for 20% more Dodge, except since you already have an item that adds Dodge, it won't be 20%. More like 14 or 15%. Get another Phantom Dancer. This'll add about 9 or 10% dodge. Another will be like 6 or 7.

In other words, stacking dodge isn't always smart (unless you're Jax).

Max dodge i've had was with a Sivir, wanted to test it. I ended with 81% Dodge Chance.
All above about dodge is rigth, i've tested it ^^