Trapped in the Web

At the beginning of each opponent's end step,
put a web counter on each creature that attacked
this turn. (A creature with one or more web counters
can't attack or block unless its controller pays {1} for
each of those counters.)
Attracting vibrations - At the beginning of your
upkeep, reveal the top X cards of your library,
where X is the total number of web counters on
all creatures. Put up to one Spider card from
among them into your hand and the rest on the
bottom of your libra