Note that cracking a fetchland counts as searching their library, so folks might not break that Terramorphic Expanse or their Polluted Mire unless they are needed, which is still a win for you as you slow them down
The deck will still have legs, especially if you replace them with more combat-oriented slivers like Spiteful Sliver or more recursion like Dregscape Sliver
23.6 Reimbursements (net down) If a payment to a party under this agreement is a reimbursement or indemnification, calculated by reference to a loss, cost or expense incurred by that party, then the payment will be reduced by the amount of any input tax credit to which that party is entitled on the acquisition of the taxable supply to which that loss, cost or expense relates
These arent always the most powerful cards overall, but often the most interesting
If you do yourself and average of 0.33 damage a turn and your average game takes 6 turns you can assume your life total is closer to 18 than 20 in reality