Unchecked Growth

Read off the rate alone, this is a generous but unremarkable combat trick: +4/+4 at instant speed, the kind of swing that wins a race or punishes an overcommitted block. What sets it apart is the Arcane line on the type, doing its work in two places the raw stat boost never shows. First, the Arcane tag makes this a legal host: any spell carrying Splice onto Arcane can fold its effect into the same cast, so a deck built around Arcane density gets to point a Glacial Ray or another spliceable spell at a target and stack the pump on top without the host card mattering on its own. Note the direction: this spell has no splice cost itself and never rides another spell. It is the thing other spells ride. Second, the conditional trample is the tribal payoff layered underneath. When the target is a Spirit, the +4/+4 stops being a blocker-friendly blowout and becomes lethal pressure that runs over the chump. Two design ideas occupy one slot, neither visible in the type line's pump number: it is the Arcane host a splice-density deck casts to soak rider effects, and it is the finisher a Spirit deck aims at its evasive threat. Strip the Arcane subtype and this is filler. Keep it, and the card is a connector.