Name:Rona, Herald of Invasion
ManaCost:1 U
Types:Legendary Creature Human Wizard
PT:1/3
T:Mode$ SpellCast | ValidCard$ Card.Legendary | ValidActivatingPlayer$ You | Execute$ TrigUntap | TriggerZones$ Battlefield | TriggerDescription$ Whenever you cast a legendary spell, untap CARDNAME.
SVar:TrigUntap:DB$ Untap | Defined$ Self
A:AB$ Draw | Cost$ T | NumCards$ 1 | SpellDescription$ Draw a card, then discard a card. | SubAbility$ DBDiscard
SVar:DBDiscard:DB$ Discard | Defined$ You | Mode$ TgtChoose | NumCards$ 1
A:AB$ SetState | Cost$ 5 BP | Defined$ Self | Mode$ Transform | SorcerySpeed$ True | AILogic$ Always | SpellDescription$ Transform NICKNAME. Activate only as a sorcery. ({B/P} can be paid with either {B} or 2 life.)
SVar:BuffedBy:Card.Legendary
DeckHas:Ability$Discard|Graveyard
AlternateMode:DoubleFaced
Oracle:Whenever you cast a legendary spell, untap Rona, Herald of Invasion.\n{T}: Draw a card, then discard a card.\n{5}{B/P}: Transform Rona. Activate only as a sorcery. ({B/P} can be paid with either {B} or 2 life.)

ALTERNATE

Name:Rona, Tolarian Obliterator
ManaCost:no cost
Colors:blue,black
Types:Legendary Creature Phyrexian Wizard
PT:5/5
K:Trample
T:Mode$ DamageDone | ValidTarget$ Card.Self | Execute$ TrigExile | TriggerDescription$ Whenever a source deals damage to CARDNAME, that source's controller exiles a card from their hand at random. If it's a land card, you may put it onto the battlefield under your control. Otherwise, you may cast it without paying its mana cost.
SVar:TrigExile:DB$ ChangeZone | Origin$ Hand | Destination$ Exile | DefinedPlayer$ TriggeredSourceController | Mandatory$ True | ChangeType$ Card | Hidden$ True | AtRandom$ True | RememberChanged$ True | SubAbility$ DBRonaLand
SVar:DBRonaLand:DB$ ChangeZone | Origin$ Exile | Destination$ Battlefield | ChangeType$ Land.IsRemembered | Hidden$ True | Optional$ True | GainControl$ True | SubAbility$ DBRonaPlay
SVar:DBRonaPlay:DB$ Play | ValidZone$ Exile | Controller$ You | Valid$ Card.IsRemembered | ValidSA$ Spell | WithoutManaCost$ True | Optional$ True | SubAbility$ DBRonaCleanup
SVar:DBRonaCleanup:DB$ Cleanup | ClearRemembered$ True
SVar:HasCombatEffect:TRUE
Oracle:Trample\nWhenever a source deals damage to Rona, Tolarian Obliterator, that source's controller exiles a card from their hand at random. If it's a land card, you may put it onto the battlefield under your control. Otherwise, you may cast it without paying its mana cost.
