Item name: Mask of the Betrayer/ Beatrix's Spite
Purpose of item: give mages added burst damage (primarily to squishies) while gating the item's snowball potential.
Recipe:
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Stats:
70 ap
20% cdr
150% base mana regen
Unique Passive: Eyes of Pain - +15 magic penetration
Unique Active: Spellspring - consume (20 x champion level mana) to gain (x ap/level) for the next (x) seconds. Additionally, abilities against enemy champions deal an additional (Y magic damage/level) that stacks over the duration. (i.e. (Y) damage on the first spell, (Y)x2 on second, (Y)x3 on third, (Y)x4 on 4th). Auto attacks deal half of this damage. Spell casts during Spellspring are half cost. (45 second cooldown).
Unique Passive: Spellfall - after Spellspring has been used your mana costs are doubled for the next (x) seconds.
Possible Concerns: Though I have left out a lot of numbers for this item I'm still worried about the power it can give.
This item gives magic penetration to enhance spell damage to low mr targets, something ap assassins typically don't have outside of
or runes.
The active consumes mana to gate the use of the item on bursty mages whenever they please.
The additional stacking damage is to incentivize players to get another few spells or auto attacks out before the active is over and put the bursty mage in a situation where they may be in more danger to finish off a target.
The spellfall passive creates another drawback to using the active and will leave assassins with fewer options to get away if they fail an assassination or will leave them mana starved if they attempt to go back in too soon.