If the target of Synthesizer Labship’s second ability was already a creature, its base power and toughness will become 2/2 until end of turn. This overwrites any previous effects that set its base power and/or toughness to specific values. Any power- or toughness-setting effects that start to apply after Synthesizer Labship’s second ability resolves will overwrite this effect. Effects that otherwise modify the target’s power and toughness, including +1/+1 counters, will still apply no matter when they took effect.