"Does each pledge level include ALL previous rewards?"

(For example, the "Experiment 350" ($350) pledge level includes all of the rewards from the Experiment 15, 35, 50, 75, 100, 150 and 250 reward levels. It's a lot of rewards.)

Unless otherwise specified, all reward packages above the $500 pledge level also include all of the rewards from the lower tier packages – but don't include the additional rewards from reward packages ABOVE Experiment 500. 

(So, the $2500 level DOES include all of the rewards up through the $500 level, not doesn't include the unique rewards offered at $800, $1000 or $1250 levels.)

For this campaign, the only STANDALONE PLEDGE levels are Experiment 85 ($85) and the "I PREFER THE ORIGINALS" package ($525), which only contain the specific rewards listed in their description on Kickstarter.

Here's the graph that we shared on Kickstarter showing what was included with each level:

*The only rewards that DON'T stack are those which get UPGRADED as you increase your pledge level – in particular, the GIZMOPLEX PASSES and the MST3K CHALLENGE COINS. For example: Experiment 75 includes a Gizmoplex Pass valid for 9 months total, but doesn't ALSO include the 3-month and 6-month passes offered in the lower levels. And the Challenge Coins? Well... let's just make that its own FAQ, huh?