Enchant creature At the beginning of your upkeep, sacrifice Serra Bestiary unless you pay {W}{W}. Enchanted creature can't attack or block, and its activated abilities with {T} in their costs can't be activated.
"I was there when Phyrexia doomed Serra's realm with a single touch. I was there when Yawgmoth tried and failed to conquer Dominaria. And I will still be here when Elesh Norn lies dead."
At the beginning of your upkeep, you may put a verse counter on Serra's Hymn. Sacrifice Serra's Hymn: Prevent the next X damage that would be dealt this turn to any number of targets, divided as you choose, where X is the number of verse counters on Serra's Hymn.
Serrated Arrows enters the battlefield with three arrowhead counters on it. At the beginning of your upkeep, if there are no arrowhead counters on Serrated Arrows, sacrifice it. {T}, Remove an arrowhead counter from Serrated Arrows: Put a -1/-1 counter on target creature.
Whenever Serum Tank or another artifact enters the battlefield, put a charge counter on Serum Tank. {3}, {T}, Remove a charge counter from Serum Tank: Draw a card.