Here is the full list of all 30 Seraph achievements.
Upgrade a Blessing to rank 5.
Kill an 'enhanced' Elite (Bloody, Tainted, Dark).
Kill the Herald.
Equip a Miracle other than Orb or Repel.
Unlock a weapon, Ward or Miracle through Transmutation
Destroy a Fountain of Terminus.
Attach a Shard to an Oath.
Unlock Daemonsight through Transmutation
Kill 88 Daemons.
Slay a Lieutenant of Terminus.
Score among the top 75% on a Daily challenge.
Collect 25 story logs.
Post a score in Survival mode
Kill 50 enemies under the influence of the Double Damage Orb
Transmute the MKII version of each weapon.
Defeat the final threat to Seraph.
Kill the Herald at difficulty 6.0 and above.
Score among the top 25% on a Daily challenge.
Collect 50 story logs.
Collect 75 story logs.
Transmute a MK4 weapon.
Reach 6 pips on the difficulty meter.
Reach difficulty 8.0 in Survival or New Game.
Kill 888 Daemons.
Kill 8,888 Daemons.
Reach difficulty 9.0 in Survival or New Game.
Score among the top 10% on a Daily challenge.
Obtain a Supreme Shard.
Defeat the final threat to Seraph at difficulty 8.0 and above.
Seraph is reborn.