Another Altar Tier means crafting another Blood Orb, the Magician Blood Orb can be crafted by placing a gold block into an Altar with 25,000 LP (you may need to add a few Runes of Capacity around the Altar, around 8).
You will need to ensure you have the required amount of LP in your Altar otherwise the orb will not craft and you will lose any blood that was in the Altar. Alternatively, you can combine Regeneration effects and the Incense Altar to refill a too-small altar tank part-way through the craft, though the timing can be finicky.
This blood orb can hold up to 150,000 LP and also enables you to craft a few new items. Remember to bind this orb to yourself by right-clicking it.